Is the undergraduate research experience (URE) always best?: The power of choice in a bifurcated practical stream for a large introductory biochemistry class

Authors

  • Susan L. Rowland,

    Corresponding author
    1. School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia
    • School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia
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  • Gwen A. Lawrie,

    1. School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia
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  • James B. Y. H. Behrendorff,

    1. School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia
    Current affiliation:
    1. Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD 4072, Australia
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  • Elizabeth M. J. Gillam

    1. School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, QLD 4072, Australia
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Abstract

Science undergraduate courses typically cater to a mixed-learner cohort, with a diversity of motivations and skills. This diversity introduces pressure for designers of the practical laboratory curriculum. Students who are struggling with the course need a series of tasks that begin simply, and transition to more conceptually difficult material. More capable students need opportunities for conceptual extension and creative activity. In this report, we examine an approach we have used to address this problem in the context of a large introductory biochemistry undergraduate class. Rather than attempting to compromise on a single practical series for our 470 students, we devised two parallel but equivalent practical streams and offered students their choice of laboratory experience. One stream (called Laboratory Experience for Acquiring Practical Skills) was designed to allow acquisition of a range of common biochemistry and molecular biology laboratory skills. The other (called Active Learning Laboratory Undergraduate Research Experience) was designed to offer an authentic (but scaffolded) undergraduate research project. We discuss the ramifications and implications of our approach in terms of funding, staffing, and assessment while also examining student motivation, satisfaction, and skills acquisition. We present data supporting the practical and pedagogical value of laboratory exercise streaming to meet the diverse needs of students. We suggest a framework that can be used to pre-emptively identify and address problems associated with a bifurcated practical series and increase the sustainability of the approach.

The practical laboratory is central to an undergraduate science education [1]. The types of learning that occur in an undergraduate laboratory can (and do) range from the simple improvement of practical skills, to the development of an abstract understanding of the nature of science. There is evidence that the learning gains achieved by students are affected by the design of the laboratory exercise [2], and this idea (in theory) is well accepted in the literature. According to the dogma, a traditional “cookbook” laboratory exercise, for example, is likely to produce only gains at the lower points of the cognitive scale as defined in Bloom's Revised Taxonomy [3]. In contrast, a research-driven laboratory learning experience has potential to produce students with an increased ability to think in an abstract manner, define and investigate their own research problems, and develop an understanding of what it means to “be a scientist”.

There have been widespread recommendations that undergraduate science teaching should adopt research-based learning as standard [4]. This has led to a wave of implementation and debate around student-centered, inquiry-based, and research-based laboratory programs [5–7]. Contexts for these experiences range from traditional laboratory programs, with a small amount of included inquiry to a stand-alone undergraduate research experience (URE), or internship, where students work in a professional research laboratory for a period of days, weeks, or months. The internship has been proposed as the ideal, authentic learning activity for the development of science skills.

URE advocates claim that laboratory UREs give students the opportunity to make significant gains in problem-solving and critical-thinking abilities, but the evidence for these cognitive gains is limited in the tertiary context [8]. Certainly, the majority of students who complete UREs are positive about their experience, but they rarely report gaining higher-order research skills such as an awareness of the provisional nature of scientific knowledge and an understanding of how to formulate research questions [8–12]. Instead, the major benefits of UREs appear to be an increased awareness of research (both in terms of the physical mechanics of how to do experiments and the role of research in society), partial induction into the culture of science, and improvements in time-management skills [8, 9, 13].

The URE experience is not universally positive. Some students develop the feeling that science is boring, lonely, or just too difficult, particularly if they have been poorly supported by their research supervisor in a professional research laboratory environment [13, 14]. Some students finish their URE with the sense that they are inadequate, and that “research is the last thing I want to do next year” [13].

There are several potential stresses associated with an independent URE for an undergraduate student. First, the URE often requires more time in the laboratory, on a per-semester basis, than a regular course. Second, the process of finding a URE supervisor in a university, negotiating aspects of the project, and finding one's way around the new, professional laboratory are all large “socialization” LEAPS. Although all of these experiences represented authentic learning opportunities for the motivated student, even high-achieving students in elite research programs report they are stressed by these processes [13]. For a shy, or less-confident student, these hurdles may be “deal-breakers” that stop the student engaging with research at all. This is particularly so if they feel alienated from the research process or are under time pressure from work and other studies [14, 15]. One must also consider the effect of an untrained, stressed, and possibly immature undergraduate student on the professional laboratory environment. Although some undergraduate students are an asset to a laboratory, some are a liability. They require input of training time, their experimental techniques and results are often unreliable, and they can use up precious (and expensive) laboratory resources while failing, repeatedly, to complete a task. For many student/supervisor combinations, the independent project in a professional laboratory is not the place to begin research [13]; indeed, some academics are unwilling to take undergraduate students into the laboratory until they know the student has some prior research experience.

An alternative route to the independent URE is the provision of a more controlled, scaffolded, and lower-stakes research project in a regular undergraduate course laboratory series. If tutors are provided to facilitate the research project, then students no longer have to find their own supervisor. If the URE is scheduled only in agreed contact hours for the course, the students may feel less stressed by unpredictable time requirements. If some element of “success” can be built into the experiments, this will likely mitigate the sense of failure that students often associate with research experiences. If the experience is well-facilitated to encourage peer support, students may be able to develop a cohort experience and engage in peer-to-peer teaching, rather than relying on variable individual academic input, during their early research training.

For a course coordinator who is designing this type of experience into on-course laboratory sessions, there are additional considerations. In large, introductory, undergraduate science courses, there are many students who do not want to experience research. From a course coordinator's perspective, there may be little benefit in heavy investment in such students; they may be better served with a structured, predictable laboratory exercise that they can complete simply while gaining relevant skills and understanding, without the additional effort of “research.”

At our institution, we routinely teach early-year undergraduate science courses with enrollments of 400–1,400 students, and we offer practical experiences in most of these courses. Our large first- and second-year undergraduate courses in Chemistry, Biology, Biochemistry, and Genetics regularly cater to students from between 10 and 30 different programs of study. Clearly, these students arrive in the courses with a diverse range of academic abilities, goals, and prior experiences. This creates challenges for us as course designers.

The role of practical learning in first-year (freshman) science courses is currently under the spotlight of the Australian Council of the Deans of Science with recommendations that the laboratory learning experience should “address explicitly, by streaming or other means, the diversity of students' prior knowledge and experience” [16]. Although this recommendation has been made, the guidelines for how to do it have not been laid out. This recommendation raises many issues. How do we acknowledge the past experience of our students in our experimental exercise design? What do students in undergraduate courses really want from their laboratory experience? Is what they want and what they need the same thing? If laboratory experiences are streamed, is it possible to make them equivalent within the one course?

Student feedback on several iterations of laboratory programs at our university has led us to propose that a single experimental laboratory series leads to confusion for the weaker students and to boredom for the stronger ones, resulting in widespread disengagement. A differentiated program of laboratory learning seems like a reasonable way to address this diversity in learners. The solution we propose is that students are offered a choice between a traditional laboratory program enriched with learner-centered exercises and an authentic URE that enables students to apply and extend their practical process skills. Both of these options should provide students with a learning experience that incorporates some elements of “high impact educational practice” as defined by Kuh [17]. Allowing students to self-determine their laboratory experience is likely to increase their intrinsic motivation (including positive affect, feelings of competence, and sense of personal relevance of the experiments) [18]. Consequently, we suggest that students will be more satisfied with a bifurcated experimental series where they are allowed to choose their own pathway.

We report here our first attempt to deliver a bifurcated practical stream in a large second-level biochemistry course that delivers different, but mostly equivalent, learning experiences for our mixed cohort. Two questions underpin our investigation: (i) Do students who complete separate laboratory routes in the same course experience the similar perceptions of gains in experimental skills?; (ii) Can we improve student satisfaction with a course by providing a choice of laboratory experience?

We present data to support a recommendation of streaming laboratory experiences within a single course. It appears to be sought by students, and possible for universities. We suggest a framework that can be used to pre-emptively identify and address problems associated with a bifurcated practical series and facilitate practitioner implementation of the approach.

PROJECT CONTEXT

The context for this study is a publicly funded, research-intensive university located in Brisbane, Australia. In 2010, the institution had 43,831 students, 4,561 of whom were enrolled through the Faculty of Science.

The subject of this article is the second-level course Biochemistry and Molecular Biology (coded BIOC2000), which caters to 450–500 students per annum. More than half of these students are enrolled in programs of study through the Faculty of Science. A significant minority, however, come from a diverse set of non-science-majors programs (including Journalism, Engineering, Business, Medicine, Food Technology, Education, and Law). Our consistent challenge has been to cater to all of these students from a lecture content and laboratory experience perspective. The aim of the project reported in this article was to adapt our undergraduate laboratory learning experience to address the diversity of our learners in BIOC2000.

BIOC2000 (like most of the undergraduate courses at our institution) has a schedule of three hours of lecture and 3 hr of laboratory (or “practical”) per week over a 13-week semester. The accommodation of public holidays means that 2 weeks are lost per semester from the laboratory timetable. In 2010 (and previous years), we used a traditional laboratory exercise in BIOC2000, which ran for 9 weeks total (27 h; Table I). Because of the large course enrollment in BIOC2000, the 3-h laboratory sessions run eight times per week (Monday pm, Tuesday, Wednesday, Thursday am and pm, Friday am) in a large laboratory that holds up to 90 students. Students work in “tutor groups” of 15–16 students with one tutor. Tutors are usually fourth-year (honors), masters, or PhD students. The academic in charge of the course conducts a training session for the tutors of 1 h per week. The academic visits some laboratory sessions for short periods of 15–20 min but does not teach the sessions personally.

Table I. Layout for experimental laboratory series in BIOC2000 (2010 iteration)
WeekActivity
1Laboratory induction and pipetting revision
2Students prepare plasmid DNA minipreps, for two unknown clones then set up diagnostic PCR and RE digest reactions using directions in their laboratory book. They streak bacterial cells on L-agar for GFP color production.
3Students prepare, electrophorese sample on, and analyze, an agarose gel to determine banding patterns for plasmids. Students examine streaked cells for GFP production.
4Round-up, final analysis, and results compilation for all students' clones. Students decide which clones will be best for production of GST-GFP fusion protein for later stages of the practical.
5Protein bioinformatics exercise
BreakMid-semester break (1 week)
6Laboratory staff prepare E. coli cell lysates with overproduced GST-GFP fusion protein. Students use glutathione-affinity chromatography to purify GST-GFP from lysate. Laboratory staff cleave the fusion on-column to release GFP. Students keep frozen aliquots of all fractions for analysis and complete a workshop on protein purification theory.
7Students use SDS-PAGE to examine purification fractions for GFP purity and yield. They quantitate purified GFP protein using Nanodrop, spectrophotometer, and BCA assay.
8Students use a CDNB assay to determine how much GST was in the original E. coli cell lysate (using the frozen crude lysate fraction from Week 6).
9Calculations for protein chemistry (in laboratory). Students reconcile their results from the different assay methods to determine their % recovery of GST from the cell lysate.
13Final report on entire practical series due Week 13 of semester.

RATIONALE FOR INTERVENTION IN THIS COURSE

The learning objectives of the 2010 traditional laboratory series were for students to obtain basic molecular biology and protein chemistry skills by completing a project where the experimental results obtained in early weeks were used as starting material for experiments in the later weeks. Because the experiments formed a continuum, we hoped that students would develop a sense of ownership over their experiments and would invest effort in the laboratory.

In the 2010 experiments, students were given bacterial clones, which contained a pGEX-2T-based plasmid [19]. Some of the plasmids contained an inserted gene that encoded a GST-GFP fusion protein with a thrombin-cleavable linker between the fusion partners. Some clones just carried pGEX-2T. The students had to determine which plasmid was in each of two E. coli strains, using a combination of restriction enzyme (RE) digestion, PCR amplification of target genes, and examination of cells for green color. Detailed protocols for each analysis method were provided in the laboratory manual, and students were generally provided with master mixes for their enzymatic reactions to reduce the amount of pipetting time in each practical.

After students identified the correct clones, the cells were induced to produce the GST-GFP fusion protein (by the laboratory support staff). The students were given the cell lysate, and they purified the fusion protein using affinity chromatography, saving fractions for later analysis. They then completed a variety of assays to examine the yield and purity of the GFP obtained from the chromatography. They also compared this to the amount of GST-GFP fusion protein they had before they began the purification to determine percentage recovery. Included in these experiments was an assay of the activity of the GST-GFP fusion protein toward a prototypical substrate of the GST.

Although this series of experiments provided a good grounding in many facets of biochemical practice, we developed an interest in revising the laboratory series based on several years of student feedback about second-year Biochemistry courses at our institution. The feedback from the 2010 iteration of BIOC2000 is summarized in Table II; these comments are typical of the responses collected for all previous iterations of the course.

Table II. Students' open responses about the experimental laboratory series in BIOC2000 (2010 iteration)
Responses by category and contenta# times this idea occurred (n = 346)b% overall from all ideas (n = 346)% of this category
  • a

    These responses were part of series of open comments made by students who had just completed BIOC2000 in 2010. Stimulus questions related to course assessment, the laboratory series, and sections of the course that students felt were “the best” or “needed improving.” Only the responses that related to the laboratory series are included.

  • b

    The total n equals 346 in this column. There were 297 comments received, but many contained more than one idea or suggestion.

Respondents who gave overall positive comments9527100
 were positive about laboratory sessions without giving specific reasons or thought experiments in the laboratory were relevant/interesting/useful601763
 liked the “lab lectures”; they supported understanding of experiments outside the laboratory session17518
 felt their laboratory tutor was supportive and helpful9310
 liked the experimental series structure and the sequential experiments727
 were positive about writing the laboratory report as a way of understanding the experiments2<12
Respondents who gave overall negative comments7823100
 were dissatisfied with write-up mechanism (but gave no suggestions for improvement)331042
 said the laboratory sessions were too complex and busy32941
 were dissatisfied with the experimental series (but gave no suggestions for improvement)10313
 thought the experimental exercises were too easy/simplistic3<14
Respondents who made suggestions for laboratory improvements17350100
 wanted smaller and/or more frequent write-ups for experimental material with simpler guidelines for preparation1133365
 wanted to be able to do research in the undergraduate laboratory; this included researching and deciding on different experimental approaches and designing experiments29817
 suggested a choice of practical exercises; this included experiments and laboratory assessment tailored to the students' study program25714
 wanted individual (not group) assessment of their work624

Overall, 27% of students' comments were positive about the practicals (top third of Table II). The responses indicated that students thought the experiments were interesting and useful, with a good, sequential structure. Some students appreciated having to write a laboratory report as a way of improving their understanding of the material and some commented that their tutors were helpful. In an independent survey question about tutors, 85% of BIOC2000 students in 2010 said that their tutor was prepared for the laboratory sessions. On the basis of this result, we did not see any need to change tutor training methods for BIOC2000.

Although 27% of comments relating to the practicals were positive, 23% of comments were negative. In the dissatisfied comment set, 42% related to the single practical report at the end of semester, whereas 41% indicated the laboratory exercises were too complex or busy, without enough time in the sessions to discuss the experiments or the results. Another 13% indicated students were dissatisfied with the current laboratory series (although no specifics were given about why they found the experience unsatisfying). Interestingly, a small proportion of students rated the practical exercises as too easy or simplistic; these students wanted more challenge.

A major suggestion students made for improvement of the course was the inclusion of smaller, more frequent reports for the practical series (with the provision of formative feedback). In addition, over 30% of the suggestions for improvement indicated that students (i)desired some flexibility in their practical exercises and (ii) wanted to research and design their own experiments.

DESIGNING NEW PRACTICAL COMPONENTS IN RESPONSE TO STUDENT FEEDBACK

In designing a new laboratory series for BIOC2000 in 2011, we initially worked from our hypothesis that a differentiated program of laboratory learning could address the diversity in our learners. We split the laboratory offering into two parallel and equivalent laboratory streams (Fig. 1). The structured learning activities in one stream were designed for students who wanted to focus on developing core understanding and improving their laboratory techniques. We assumed that most students would choose this stream; our informal discussions with students suggested that the majority would choose an option that looked “easier,” and that only a few wanted to pursue a research-intensive laboratory stream. We have coined the acronym “laboratory experience for acquiring practical skills” (LEAPS) for this program.

Figure 1.

Comparison of the LEAPS and ALLURE laboratory series on a week-by-week basis. The LEAPS series is shown on the left of the diagram. The ALLURE series is shown on the right. The Week of semester when each activity happened is shown vertically in the centre of the diagram (white numbers in black boxes). Sections of the series where the two streams did very similar (or the same) activities are shaded gray. The arrows in the top three layers of the diagram indicate the weeks where students could still switch from one stream to another. The length of the arrow indicates the ease with which a switching student could catch up the stream-specific material. Shorter arrows indicate a greater degree of difficulty. After the beginning of Week 4, switching was no longer possible.

The second stream included an authentic URE and was tailored toward the small number of undergrads who were considering pursuing a career in research or who wanted a controlled challenge. This stream allowed undergraduate students to work during their regular timetabled BIOC2000 laboratory hours with the aim of obtaining useful results for an extant research project at our institution. We have coined the acronym “active learning laboratory undergraduate research experience” (ALLURE) for this stream.

LEAPS STREAM: FROM TRADITIONAL FORMAT TO PARTIAL-INQUIRY FORMAT

This experimental series was modified from the traditional style series used in 2010 and prior iterations to include more inquiry components. The aim of the series was still as described in the “project context” section; however, some of the predetermined experimental approaches in the molecular biology part of the practical were replaced with components that required students to design their own experimental approaches. The protein chemistry part of the practical remained unchanged. A full pedagogical analysis and evaluation of this intervention will be reported elsewhere, but the changes are detailed briefly below for completeness:

Adaptation 1: Hands-On Plasmid Manipulations

After completing previous versions of BIOC2000, many of our students were still confused about plasmids, particularly the various genetic and functional components of plasmids, and the events that occurred at the multiple cloning sites (MCS) during gene insertion. To remedy this confusion, we developed a new laboratory exercise in which students built plasmids out of pipe-cleaners and modeling clay, then cut the plasmids and cloned “genes” into them at the MCS. Students used scissors in lieu of REs and extra pieces of pipe-cleaner to represent insert DNA. All students did this exercise (Week 2 in Fig. 1), but the plasmids built were specific for the LEAPS or ALLURE streams. The plasmid maps used as stimuli represented the plasmids that encoded the GST-GFP fusion protein (LEAPS) or the P450 enzyme (ALLURE). Students in both streams also built a pBluescript plasmid and compared it to their more specialized vectors.

Adaptation 2: Students Choose and Plan Their Own Restriction Digest Mechanism

In previous iterations of BIOC2000, students had been told which REs to use to cut their unknown plasmids. In the new practical, we replaced this with an open experimental plan. Students were given the two plasmid maps (pGEX-2T and pGEX-2T plus an insert at the MCS) and the option of three REs that they could use (BamHI, EcoRI, and PstI). All of these enzymes function in the same buffer system, so students could use any one (or combination of) enzyme/s to digest their unknown plasmids. Positive and negative control plasmids (pGEX-2T plus an insert at the MCS and pGEX-2T, respectively) were also supplied for digestions so the students could use them as a reference. After devising their own digestion strategy and protocol (Week 2 in Fig. 1), students digested their plasmids and electrophoresed them as for previous iterations (Weeks 3 and 4 in Fig. 1). There was no “right” or “wrong” way to digest the plasmids, but some digestion strategies were more diagnostic than others.

Adaptation 3: Students Choose Primers and Plan Their Own PCR Reaction

In previous iterations of BIOC2000, students had been supplied with a master mix containing the correct primers needed to amplify the MCS region of pGEX-2T and any inserted genes. In the new practical, students were presented with the DNA sequence around the MCS of pGEX-2T, and the sequences of six potential primers. Only two were correct. The others were inverted (running 3′ to 5′ with respect to the target) or they annealed to the wrong strand to allow amplification. Students were allowed to freely choose any two of these primers for their diagnostic PCRs. Tubes of all primers were provided in the laboratory. Positive and negative control plasmids were supplied (as above) as templates. After choosing the primers, students developed a protocol for the PCR reaction mixture (Week 4 in Fig. 1). In Week 5, students were provided with a master mix containing the other components needed for the experiment. They added their primers and templates to begin the PCR reaction. In Week 7, the reaction results were analyzed using agarose gel electrophoresis.

ALLURE STREAM: INTRODUCTION OF A URE “DETERMINANTS OF CATALYTIC PROMISCUITY IN THE CYTOCHROMES P450”

The research undertaken by author EMJG's group focuses on the cytochromes P450. An extension of this work was chosen as the project for ALLURE. P450s are a superfamily of hemoprotein enzymes that generally catalyze the monooxygenation of organic substrates. They have been termed “the biological blowtorch” [20], catalyzing at least 60 different types of chemical reaction [21]. This functional plasticity is reflected in their wide phylogenetic distribution and diversity of roles in nature [22].

Research in the Gillam laboratory has been directed at exploiting this catalytic versatility and substrate promiscuity to develop libraries of P450s for potential application as biocatalysts. The group uses DNA family shuffling [23] to produce libraries of mosaic mutants of two or more human P450s from the same subfamily [24]. However, as with most directed evolution projects, screening of the large number of mutants in the libraries tends to be the major factor limiting progress.

This limiting step offered an opportunity for a group of undergraduate students to participate in real research and carry out experiments to obtain results that were genuinely useful for the overall project. Essentially, we tasked the students with a very preliminary metabolic characterization of a few mutant enzymes (each towards up to three marker substrates). The experimental sequence used for the project is shown in Fig. 1.

Students were responsible for designing, implementing, and troubleshooting their own experiments independently after a preliminary modeling session under the guidance of an expert tutor (author JBYHB). The tutor remained with the students throughout the semester to offer continual guidance and structure. The enzyme assays were designed to be done using intact bacterial cells containing the expressed P450s in a catalytically competent system. The students were supplied with the relevant cultures prepared freshly by the tutor. The substrates chosen were metabolized to either fluorescent (alkoxyresorufins) [25, 26], luminescent (luciferin derivatives) [27], or colored products (p-nitrophenol, indole) [28, 29], all of which were easily screened in 96-well plates or in culture. The mutants were chosen from a library created by shuffling two P450 forms, CYP1A1 and CYP1A2, as described previously [24] and prescreened for adequate P450 expression by measurement of hemoprotein concentrations in cultures [30].

The first screening experiment (Assay 1 in Fig. 1) was performed under the direct guidance of the expert tutor and involved using luminogenic P450-Glo™ substrates. The advantage of using a P450-Glo substrate in the first assay was the very strong positive signal reported by the luminescent product in positive control assay. This allowed students to very clearly see positive results against minimal background signal when plotting their data, which facilitated discussion of assay sensitivity issues in subsequent sessions. In the first session, students also set up a product standard curve covering the full range of possible product concentrations that could be formed based on the concentration of substrate supplied. Students compared their standard curves to their assay results, and when their assay results only occupied a small section of the standard curve they redesigned the standard curve to test the appropriate product concentration range with better resolution.

Students then conducted a second assay (Assay 2 in Fig. 1) where they tried the same overall experiment using their choice of a fluorimetric or colorimetric assay. They carried out Assay 2 using their own experimental plans (using Assay 1 as a template). The assays (fluorimetric and colorimetric) were less sensitive than Assay 1 but the students compensated for this by referencing their standard curves and looking at reproducibility of replicate assays versus negative controls. Positive controls were not provided by the tutor for the first iteration of Assay 2 and were only made available if requested by students during an assay troubleshooting workshop in Week 7 (which they did after they conferred as a group during the session).

After students had decided which of their clones had interesting catalytic abilities, they streaked the E. coli cells on L-Agar plates, extracted the plasmids that carried the P450 genes, then sent these for forward and reverse DNA sequencing. They analyzed their DNA sequences to determine the genetic heritage of each useful clone.

Issues such as the need to repeat experiments to demonstrate reproducibility, experimental error, experimental artifacts, and the importance of both negative and positive controls, arose naturally when students analyzed and interpreted their experiments. The opportunity to repeat experiments that did not “work,” and to obtain genuinely novel results that were not previously known, reflected the reality of biochemical research. The students were able to obtain sufficient, reliable results such that, for each mutant, we could confidently conclude whether or not the enzyme catalyzed a particular assayed reaction.

SUMMARY OF HOW THE CHANGES DEALT WITH MAJOR ELEMENTS OF PRIOR STUDENT FEEDBACK

  • 1Students found the 2010 practical series too complex and rushed. In the new laboratory structure, the experiments have been expanded over two extra weeks for both LEAPS and ALLURE.
  • 2Students cited the single report at the end of semester for the experimental assessment as being stressful and confusing. In the new assessment structure, the report is divided into two shorter submissions due in Weeks 9 and 13 of semester for both LEAPS and ALLURE. We provided summative and formative feedback on the first report, consistent with accepted good teaching practice [31]. Both LEAPS and ALLURE had parallel (and equivalent) assessment so that neither set of students gained a time or effort advantage over the other. The assessment framework for the parallel streams is given in Table III.
  • 3Students wanted to be able to design their own experiments. This was addressed through inclusion of an inquiry component in the LEAPS practical stream and provision of substantial freedom in experimental design in the ALLURE series.
  • 4Students liked getting a range of experimental experiences in their laboratory sessions. In both the LEAPS and ALLURE streams, we provided opportunities for all students to acquire skills in major biochemistry and molecular biology techniques. These included DNA manipulations, use of plasmid maps, agarose gel electrophoresis, bioinformatics, SDS-PAGE protein analysis, enzyme assay, and protein quantitation.
Table III. Assessment mechanism for LEAPS and ALLURE practical streams
W'k dueLEAPS assessment itemaALLURE assessment itema% of course grade and av. aggregates
  • a

    Marking rubrics and submission guidelines used for these items are available upon request from the authors.

1–11Laboratory attendance, completion of prework, and effort in the laboratory. Tutor marks each student each week out of 5Laboratory attendance, completion of prework, and effort in the laboratory. Tutor marks each student each week out of 5.9% of grade LEAPS average/55 = 53.5 ± 4.6
A detailed criterion-based marking scheme is supplied to tutors and students for this item.A detailed criterion-based marking scheme is supplied to tutors and students for this item.ALLURE average/55 = 53.9 ± 2.5
9Report (hand-written) that covers the molecular biology/DNA component of the laboratory.Students are required to hand in photocopied sections of their notebooks pertaining to key parts of the experimental design and results completed so far.10% of grade
Report is structured in 12 sections, with each section being a simple, stand alone item (eg: include a labelled picture of your DNA gel where you analyzed your PCR reaction. Instructions on how to label would be detailed).This piece is less work than the LEAPS assessment; however, it does require individual students to keep a quality laboratory book during each session. The LEAPS students can keep a less detailed book.LEAPS average/50 = 41.9 ± 6.7
This report was designed to mimic a well-kept laboratory notebook and develop appropriate record-keeping habits.The ALLURE students also spend more time each week in prework and planning outside the laboratory than do the LEAPS students.ALLURE average/50 = 42.7 ± 5.4
13Report (hand-written) that covers the protein chemistry component of the laboratory.Final report in the form of a Molecular Cell short paper that includes all relevant experiments, results, and conclusions from the semester. 6 page limit.10% of grade
This report was also designed to mimic a well-kept laboratory notebook. It included questions that required the students to explain key elements of the practical series.Students are provided with example Molecular Cell short communications, and Molecular Cell Instructions to Authors but few other specifics are given, to allow creativity.LEAPS average/50 = 37.0 ± 8.6
Calculations for the enzyme assays and protein recovery estimations were broken down into logical sections to facilitate student completion. We found that in prior years students would just leave out the calculations and lose marks, rather than attempting them wholesale.Students also had to answer 6 questions that asked for brief explanations of key elements of the practical series.ALLURE average/50 = 40.2 ± 3.6

IMPLEMENTATION AND ANALYSIS OF THE BIFURCATED PRACTICAL STREAM

Enabling Student Selection of Laboratory Streams

All students in BIOC2000 (n = 496 at the beginning of semester) were provided with the option of self-selecting into one of the two possible laboratory routes (LEAPS or ALLURE).

Announcements about the alternative practical streams were made by general email to the enrolled students starting 4 weeks before the beginning of semester and continuing at a rate of approximately one email per week until the third week of semester. The initial (and the second) announcement contained the FAQ document shown in Supporting Information Fig. S1. This document was also included in the laboratory manual for BIOC2000.

Students were asked to indicate their interest in the ALLURE sessions by email, including the session time that they wanted to attend on a regular basis. Four sessions of ALLURE were offered during each week (Tuesday and Thursday am and pm) with a total of 60 student places. Eight LEAPS sessions were offered during the week (Monday pm, Tuesday, Wednesday, Thursday am and pm, and Friday am) with a total capacity of ∼440 students (the remainder of the course enrollment).

When the announcement series commenced, not all possible students were enrolled in the course (∼50% of students do not enroll in courses until the week before the beginning of semester). This meant that some students received more announcements than others and had a greater opportunity to enroll in ALLURE. This variable is beyond our control.

We were concerned that we would be unable to fill all 60 of the available ALLURE places; however, within 3 weeks of sending the first email, we had to close applications for ALLURE because of overwhelming demand for the sessions. We established 60 student names on the ALLURE session lists, with a further wait list of approximately five students per session (80 students overall). We stopped taking names 1 week before semester began. Students who were on the ALLURE lists were informed individually by email of their status. All enrolled students were sent a general email indicating that they were in LEAPS unless they had been informed otherwise.

The first 3 weeks of the laboratory series were designed so that students in the LEAPS and ALLURE stream pursued similar experimental and theoretical trajectories until Week 4. This meant that students who started ALLURE, then decided they did not want to complete the stream, could switch back to LEAPS in the first 3 weeks, and be replaced by a LEAPS student who was on the waiting list. This happened with two of the 60 initial ALLURE students. The ease with which a student could switch is indicated by the arrows on Fig. 1 (longer arrows mean an easier transition). After the beginning of Week 4, it was not possible to switch, because the experimental streams diverged at this stage.

PRACTITIONER ASPECTS OF IMPLEMENTING THE TWO LABORATORY STREAMS

LEAPS and ALLURE students all completed their laboratory work in a single, large undergraduate laboratory on adjacent benches during the same time slots.

The two laboratory experiences were designed, as much as possible, to provide similar skills exposure (e.g., SDS-PAGE, agarose gel electrophoresis, DNA sequence manipulation, protein assays), although we could not provide exactly equivalent experiences in both streams. Students completed their laboratory work as shown in Fig. 1. Both streams of students completed their laboratory exercises in a total of 11 weeks (33 hr in the laboratory). Both streams of students handed in a report in Weeks 9 and 13 of semester (see Table III and Fig. 1).

The LEAPS experiments (∼440 students) were supported by the departmental technical staff in charge of the undergraduate practical laboratories. This is the usual procedure for the BIOC2000 practical series, and a set budget is assigned to this each year by the school. The ALLURE experiments required specialist technical skills that were provided by the tutor in charge of the ALLURE groups (JBYHB). Apart from teaching and marking time, JBYHB worked approximately 70 preparatory hours during the semester and was paid at usual tutor rates according to the UQ award. This expenditure was covered by a Teaching and Learning Grant to authors SLR and GAL; this grant is not ongoing. All troubleshooting and student support for the ALLURE stream was performed by JBYHB. Practical report submissions were marked by JBYHB (ALLURE) and by SLR and a support group of tutors (LEAPS).

EVALUATION OF THE EFFICACY OF A BIFURCATED LABORATORY STREAM IN TERMS OF SELF-EFFICACY AND SKILLS GAINS

Student perception data were gathered and evaluated through an online pretest self-efficacy survey (delivered in Week 1 of semester) and post-test survey (delivered in Week 13 of the same semester) managed through SurveyMonkey. Only student responses to questions designed specifically for this study are reported in this article. Students were offered an incentive of 1% bonus course mark for completing both the pretest and the post-test surveys, which resulted in a completion rate of 77% (368 of 476 students enrolled at the end of semester completed both surveys). Of these 368 students, 345 gave consent for analysis of both their survey response sets. Students who completed the ALLURE module are designated “ALLURE” (n = 45) and those that completed the traditional practical route are designated “LEAPS” (n = 300). Thus, the data reported here reflect the opinions of 75% of the ALLURE students and 72% of the LEAPS students.

Evaluation of Student Motivations for Stream Choice

Student motivations for choosing ALLURE or LEAPS were examined (Fig. 2) using a statement “I chose the laboratory stream that” and multiple answer options. Students gave their opinions of each answer option using a four-point Likert scale (strongly agree, agree, disagree, strongly disagree) with a further category called “I did not consider this in my decision.”

Figure 2.

Students' motivations for choosing different laboratory streams. The 397 students who participated in the pre and post surveys for BIOC2000 were asked to rank their agreement with the statements shown on the left of the graph. For each statement, the percentage of students who agreed or strongly agreed (mid gray), who disagreed or disagreed strongly (black), and who did not consider the statement in their decision (pale gray) are shown. Responses to each statement are reported in sets of three down the vertical axis of the figure. The top bar of each set (OA) is the overall responses from the whole class. The other two bars represent responses from science students (SC) and non-science major students (NS).

The four statements that students agreed with most strongly were (i) The stream looked like something I would be capable of doing (82% agree); (ii) The stream looked like something I would be better at (73% agree); (iii) The stream looked more structured (66% agree); and (iv) The stream looked more controlled (66% agree).

Taken by themselves, these results are somewhat disappointing; they suggest that the students are avoiding challenge, and even the option of having fun (see responses for the “fun” option in Fig. 2) in favour of a laboratory exercise that is safe, manageable, and most likely to produce the best result with the least effort. They also support the idea that a significant proportion of the students enrolled in BIOC2000 are looking for the simplest possible way to get through the laboratory component.

To further examine this finding, we separated the responses into two groups. Group one comprised the response from the 252 BIOC2000 students who are enrolled in a single degree through the Faculty of Science (B.Sc, B. Biomed. Sci, and B. Biotech). We assume students in this group are at least considering their future in a research science discipline that uses biochemistry and molecular biology. We designated responses from these students as “Science” (SC). Group two comprised responses from 145 BIOC2000 students whose major focus does not appear to be a future in a science that uses biochemistry and molecular biology. These students are enrolled in single or dual programs of study, which will not lead primarily to a “hard” science qualification. We call responses from these students “Non-science” (NS).

We compared the drivers for selection of laboratory streams for SC and NS students by determining the ratio of agree and disagree responses for each statement between the groups (data not shown). The disparities in SC versus NS drivers are best appreciated by looking at the offset between the gray “did not consider” bars for the SC and NS student groups in Fig. 2 (bottom two data sets for each statement). The four drivers where the groups differed most in their opinion were (i) The stream looked like something I would be better at; (ii) The stream let me test if I liked research; (iii) The stream let me design my own experiments; and (iv) The stream looked more interesting.

It appears from these results that students enrolled in science programs are far more interested in taking chances and exploring the possibility of research in the undergraduate laboratory than non-science majors. This theory is supported by the enrollments in ALLURE. In our 345 analyzed survey results, 41 ALLURE respondents were also SC students, while only 11 were NS. In the group of respondents who said they wanted to do ALLURE but could not because of enrollment limits, 34 were SC while only eight were NS. We conclude from these numbers that (i) only about 20% of the BIOC2000 cohort in 2010 was interested in ALLURE enrollment, and (ii) just over 70% of these motivated students are taking “hard” science programs.

This finding further underlines the need for streaming of class offerings, particularly in large undergraduate cohorts; not all of the students are keen to take on all the available learning opportunities. It makes sense to conserve scarce resources and provide extension opportunities to the students who want them, rather than to force them on everyone.

Evaluation of Changes in Students' Confidence in the Laboratory

Student confidence in their manipulative and practical skills was explored through a five-point Likert scale. The skills examined were classed as technical or analytical and are shown in Table IV. We consider a “technical” skill to be one that a 3-year-trained laboratory technician would perform in a laboratory with minimal supervision; it could be used routinely to generate a result without a significant amount of associated theoretical knowledge. In contrast, an “analytical skill” is something that requires a higher level of data interpretation, and a degree of theoretical understanding in the field.

Table IV. Skills assessed in the pre- and post-BIOC2000 laboratory series survey
Skill descriptionCodea
  • a

    Components of code are G = general laboratory skill, D = DNA-related skill, P = Protein-related skill, B = bioinformatics skill, T = technical, and A = analytical skill.

Weighing a solidL T1
Reading a scale on a thermometerL T2
Making a simple graph to display experimental data using MS EXCELL T3
Pipetting 50 μL of a liquidL T4
Determining the accuracy of a measurementL T5
Recording data in an appropriate formatL T6
Doing calculations associated with dilutionsL T7
Preparing and running an agarose gel for DNA analysisD T1
Using a plasmid mapD T2
Creating and using a standard curve for DNA fragments on a gel after electrophoresisD T3
Preparing a reaction mixture for a restriction enzyme digestD T4
Preparing and running an SDS-PAGE experiment for protein analysisP T1
Creating and using a standard curve for proteins on a gel after electrophoresisP T2
Running an enzyme assayP T3
Calculating percentage yield from a protein purificationP T4
Graphing data from enzyme assaysP T5
Deciding if one experimental approach is better than anotherL A1
Planning my own experimentsL A2
Reading and analysing DNA sequencesD A1
Interpreting the results of a DNA gelD A2
Designing PCR primersD A3
Interpreting the results of a protein gelP A1
Doing enzyme kinetics calculationsP A2
Calculations where I use an assay standard curve to determine output from an enzyme reactionP A3
Using bioinformatics methods to examine protein structure and functionB A1

These data were analyzed using standard statistical research software (SPSS). A paired sample-dependent t-test was applied to the pre- and post-data for LEAPS and ALLURE students. The data (Figs. 3 and 4) show that, before the laboratory series began, the LEAPS students generally felt more confident about their skills than did the ALLURE students (for each skill the top bar of the set is LEAPS pre while the second from top is ALLURE pre). Most students were confident about their general laboratory skills, but they reported low confidence in their DNA and protein manipulation skills, and very low confidence in their bioinformatics skills. This finding is unsurprising—100% of students entering BIO2000 have completed four to eight credit-points-worth of introductory chemistry and biology laboratories, but almost none have completed a biochemistry or bioinformatics laboratory course prior to their BIOC2000 enrollment.

Figure 3.

Levels of self-reported “technical” skills for LEAPS and ALLURE students before and after their 2011 laboratory experience.

Students were asked to rank their confidence level about each skill using a Likert scale. The response choices are shown at the bottom of the graph (each response was given a number on the Likert scale from 0–5 left to right). The average scores for LEAPS and ALLURE students pre and post BIOC2000 are shown for each skill. The definition of “technical skills” is given in the text. Skills and their codes are described in Table IV. For all skills the student self-efficacy rankings are presented as LEAPS presemester (top bar), LEAPS postsemester (second from top bar), ALLURE presemester (third from top bar), ALLURE postsemester (bottom bar).

Figure 4.

Levels of self-reported “analytical” skills for LEAPS and ALLURE students before and after their 2011 laboratory experience.

These data are generated and presented as described for Fig. 3. Skills and their codes are described in Table IV. The definition of “analytical skills” is given in the text.

After completing the laboratory program in BIOC2000, LEAPS students experienced a significant increase in confidence (p ≤ 0.001) for all skills (LEAPS “post” data is the third bar from the top for each skill in Figs. 3 and 4). The ALLURE students experienced a significant increase in confidence (p ≤ 0.001) for most skills (bottom bar for each skill in Figs. 3 and 4). ALLURE students experienced nonsignificant gains in confidence (p = 0.009 – 0.2) for six of the seven technical skills (LT1, LT3, LT4, LT5, LT6, LT7). The lack of significance stems from (i) the high level of perceived technical skill before the laboratory series, and the (ii) the small sample size for the ALLURE group (n = 45).

We used a Mann–Whitney U-test to compare the final levels of confidence achieved by the LEAPS and ALLURE students for each skill. For all but three skills, there was no significant difference between the final levels of skills perceived by the LEAPS and ALLURE students (significance level set at p ≤ 0.001). Both LEAPS and ALLURE students perceived (on average) small gains in general technical laboratory skills (LT1 through LT7), slightly larger gains on the analytical laboratory skills (LA1, LA2), and much larger gains in the DNA, protein, and bioinformatics skills. ALLURE students made significantly larger gains than LEAPS in skills that related specifically to the repetitive aspects of the URE project (PA3 and PT3), and in their perceived abilities to plan experiments (LA2). On the other technical and analytical skills, however, the LEAPS students made similar, or slightly larger, gains than the ALLURE students (as seen from Figs. 3 and 4, although the differences were nonsignificant).

In all, these results indicate that the overall gains in confidence in a variety of skills was similar for both the LEAPS and ALLURE students, even though (i) the content of only 6 of their 33 hr of timetabled laboratory work was identical, and (ii) they were assessed using different mechanisms.

Although we did not moderate the marks between the two streams, LEAPS and ALLURE students also achieved very similar overall aggregate marks for their laboratory work and reports (Column 3, Table III). This suggests that our preparation guidelines and marking rubrics are robust (we have not rigorously tested the support for this statement).

STUDENT SATISFACTION WITH THE STREAMED LABORATORY APPROACH AND WITH THE COURSE OVERALL

It is difficult to assess how much “better” the course was overall in comparison to the 2010 iteration; however, there was a significant rise in the ranking the students gave to BIOC2000 between 2010 and 2011 (3.69 vs. 4.23 of five). This improvement cannot be attributed solely to the change in the laboratory stream—we also placed a new 40% achievement hurdle on the final examination but buffered this with a mechanism of on-course assessment that allowed the students to choose assignments and gain more marks during the semester. However, it does indicate that the students were had a better opinion of the class overall in 2011 versus 2010.

In the postcourse satisfaction survey, we asked the BIOC2000 students “At the end of BIOC2000, were you happy with the laboratory stream that you did?”. Eighty-five percent of students answered “yes,” 6% answered “no,” and 10% said they were “not sure.”

These responses are reflected in the open comments that the BIOC2000 students made about their laboratory experiences. Table V shows these comments using the same format used in Table II (for the 2010 comments). From 2010 to 2011, the proportion of comments that were positive about the practical series rose from 27 to 52% while the proportion of negative comments fell from 23 to 18%.

Table V. Students' open responses about the experimental laboratory series in BIOC2000 (2011 iteration)
Responses by category and contenta# times this idea occurred (n = 150)b% overall from all ideas (n = 150)% of this category
  • a

    These responses were part of series of open comments made by students who had just completed BIOC2000 in 2011. Stimulus questions related to course assessment, the laboratory series, and sections of the course that students felt were “the best” or “needed improving.” Only the responses that related to the laboratory series are included.

  • b

    The total n equals 150 in this column. There were 135 comments received, but several contained more than one idea or suggestion.

Respondents who gave overall positive comments7852100
 were positive about laboratory sessions without giving specific reasons or thought experiments in the laboratory were relevant/interesting/useful342344
 made a positive comment specifically about their LEAPS or their ALLURE experience231529
 felt their laboratory tutor was supportive and helpful171122
 liked the “short pracs”213
 were positive about writing the laboratory report as a way of understanding the experiments213
Respondents who gave overall negative comments4018100
 said the laboratory sessions were too complex and busy231558
 were dissatisfied with the write-up mechanism (but gave no suggestions for improvement)5312.5
 were dissatisfied with the experimental series (but gave no suggestions for improvement)5312.5
 thought the experimental exercises were too easy/simplistic327.5
 did not like their tutor (language difficulties)4310
Respondents who made suggestions for laboratory improvements3221100
wanted a different/earlier due date for the final report with guidelines for preparation available earlier in semester12838
 wanted more ALLURE places opened for enrollment9628
 discussed the pros and cons of ALLURE vs LEAPS (while satisfied with their own choice, they saw benefits in other stream too)7522
 said that they thought they lacked breadth in their experience because they did ALLURE329
 found ALLURE stressful and wanted to do LEAPS instead1<13

Most of the negative comments in 2011 stemmed from a small number of LEAPS students who are confused in the laboratories. We had to remove some of the supporting “lab lectures” between the 2010 and 2011 iterations due to faculty scheduling problems, and apparently, the laboratory notes are not sufficient for students who do not process written material well. We suggest that students who are confused in LEAPS would be even more confused in ALLURE, where the laboratory manual often referred students to a primary paper and asked them to work out their own protocol.

Most ALLURE students said that they enjoyed the challenge and novelty of the URE, although some also indicated that it was stressful. Some students had misgivings associated with their choice of practical stream. In the following comments, punctuation and spelling are as written by the students.

ALLURE Student 1

I loved working in ALLURE, it was a great experience and I wish other courses would offer such a thing. I don't think I could manage doing something like ASPINS, but these small research projects were something that really gave me confidence in my ability to work in a lab and analyze results. I wish I had done CASPIE now. (Author's note: ASPINS is an advanced student program offered to high-achieving high-school students when they enter our Science courses. ASPINS students pursue an enriched curriculum throughout their entire undergraduate degree. CaSPiE [2] is offered in our first year chemistry courses [32]. Less than 10% of the freshman chemistry class opt to take CaSPiE).

ALLURE Student 2

I felt like I was missing out on learning actual course content by being in ALLURE, But, I loved the autonomy and being able to design experiments and do things that are actually “going somewhere” (as opposed to standard done-thousands-of-times experiments that seek to prove things that have already been published).

ALLURE Student 3

I feel great being in ALLURE and the difference between the two streams did not bother me at all.

ALLURE Student 4

I found it (ALLURE) confusing and stressful at times and thought I would have gotten better stress control if I had done LEAPS.

ALLURE Student 5

The LEAPS assignments seemed less stressful and the diversity in practicals seemed like more fun.

LEAPS Student 1

I didn't really enjoy first year labs, but this year, especially for bioc I really enjoyed the labs. it would have been a good experience to take part in ALLURE to see what its like to make up my own experiments, but the course made me realize I wouldn't mind doing this in the future, so I will take advantage of any offerings like this in the future.

LEAPS Student 2

I was happy with my choice in the LEAPS stream; however, given the choice again, I would have chosen the ALLURE stream. I didn't participate in the ALLURE stream initially because I was worried that my performance wouldn't be of a high enough standard compared to some of the other students.

LEAPS Student 3

I'm glad I didn't choose ALLURE.

DISCUSSION AND IMPLICATIONS FOR PRACTICE

This article describes our first attempt to introduce concurrent laboratory streams into a large introductory biochemistry class in order to cater to a mixed-learner cohort. We faced several challenges around the implementation of streaming in the experimental laboratory. These challenges, and the things we considered while dealing with them, form the basis of the LEAPS/ALLURE Issues and Implementation Framework presented in Table VI.

Table VI. 
inline image

First, we will address the important challenges associated with building equity for students, in terms of time input, grade output, and learning opportunities into the two streams. Obviously, it is not possible (or even desirable) to provide the same learning experience in two different laboratory streams, but it is important to try and build similar elements into the two streams, so that students are not disadvantaged by their choices.

We designed the two streams so that both ALLURE and LEAPS students could complete their assigned laboratory work within their 33 contact hours. We did not measure the number of hours that LEAPS and ALLURE students spent working on their assessment items or laboratory prework outside of the laboratory sessions. A more thorough analysis of future iterations should include this measurement; however, it may reflect the dedication of students to the task, rather than the minimal time to complete the required material; we suspect ALLURE students spend more time reading around the topic, for example, than do LEAPS students. There was probably more time stress on the ALLURE students (see comments from ALLURE Students 4 and 5 above) who needed to prepare their experimental plan each week before coming to the laboratory. LEAPS students just had to make a flow chart from the notes in the laboratory manual (but this is less authentic than the ALLURE experience).

In the open comments reported above, ALLURE Student 2 indicated that they were worried about their breadth of experience in one stream versus the other; this student is unlikely to be alone in their opinion. Although very few of the participating students indicated that the difference between the streams distressed them, the streaming is an issue that has to be managed sensitively. As well as the potential for “unfair” skill building in one group versus another, there is also the possibility of elitism for the small URE group and consequent amotivation in the larger traditional laboratory. This is particularly so for the 42 LEAPS students who wanted to complete ALLURE but could not get in due to class size limits. Self-determination theory [33] suggests that this group is likely to see low relatedness between their interests and their laboratory experience, because they were not able to exercise autonomy in their choice of stream.

We were concerned about these potential affective complications for our students, but in 2011 no student complained to us in written or verbal form about feeling less important or motivated, because they were in LEAPS. We suggest that the material we provided to explain the two streams (see Supporting Information Fig. S1) may have helped with this. We also gave students the names of other courses that would be implementing UREs in-class so they could take these alternate opportunities and deliberately informed students about why the ALLURE spaces were limited. We also reassured them that LEAPS was not a “second best” option; we made this clear to our laboratory tutors too, and asked them to be very careful to encourage the sense that the large LEAPS cohort was just as important as the small ALLURE group.

We designed an equivalent assessment methodology for the two streams; there was no significant difference between the final practical marks for the ALLURE and the LEAPS students. As stated above, we did not examine the hours spent by ALLURE and LEAPS students on their assessment items.

Our assessment of students' self-reported gains from LEAPS and ALLURE suggests that although the students had different learning experiences, they perceived similar changes in their confidence around experimental techniques. ALLURE students perceived slightly larger gains in skills that could be classified as “understanding the nature of science,” but the LEAPS students perceived that they had larger improvements than ALLURE in several technical skill areas. We did not perform side-by-side laboratory skill testing on ALLURE and LEAPS students to determine if these perceived skill gains are actualized; this kind of analysis was not built into the assessment scheme for the course, and it was inappropriate to ask students to volunteer for lengthy testing sessions outside the regular course hours. Such testing may also have influenced the students' perception of skill change by providing initial practice in the skill before the semester began.

Our second challenge is around using the bifurcated experimental stream to satisfy the educational needs of students while also developing positive affect toward the subject of biochemistry. Our initial concerns about the demand for ALLURE were quickly allayed by the overwhelming response from the class (as evidenced by the postcourse survey responses, the waiting lists for ALLURE, and the number of emails to staff in charge of ALLURE enrollments). We could probably have filled 100 ALLURE places from our cohort of 470, and 58 of the 60 the students who did begin ALLURE stayed with the program. Two opted to return to LEAPS in Weeks 2 and 3, and their places were filled by students on the waiting list. All 60 students enrolled in ALLURE at Week 4 finished the ALLURE stream and gained at least a passing grade in their assessment.

Our analysis of the drivers for choice of experimental stream shows that students enrolled in science programs are far more interested in an experimental challenge and authentic research experiences than those taking nonscience majors. This is understandable, and it points out an important caveat when designing laboratory experience curricula—not all students want to be challenged. This may be for a variety of reasons some of which are shown in Fig. 2. We suggest other drivers for LEAPS choice include stress from other course requirements, a prior bad URE experience, feelings of personal inadequacy, a surface-apathetic learning style [34], or just not enough interest in biochemistry to want to pursue a URE. Two students also said they did not enroll in ALLURE, because they had already done a URE in another class and they felt they should “give someone else a chance,” because there were limited ALLURE spaces.

Whatever reasons students have for choosing not pursuing ALLURE, most of them appeared to be happy with their choice (85%) and very few were definitely unhappy (6%). A much smaller proportion of students gave negative feedback about the BIOC2000 laboratory exercises in 2011 than in 2010, and the proportion of positive comments climbed steeply. This improvement in student affect from 2010 to 2011 may be, in part, due to the Free Choice paradigm first demonstrated by Brehm [35]; in the case of LEAPS and ALLURE, students may be increasing their perception of the value of their chosen stream to alleviate the cognitive dissonance associated with making a choice. Alternatively (or in addition to this), students who were able to complete their desired stream engaged in self-determination, which has been shown to have positive effects on motivation and confidence in multiple contexts ([36] and references therein). In later iterations of the course, we will study these factors in more detail, but the outcomes of this year's study remain. First, the students appear to be happier in a self-streamed laboratory experience than in an undifferentiated class, and second, there are clear differences in the drivers for stream choice between science and non-science students. This indicates that for any course with a diverse enrollment, self-streaming is likely to create more opportunities for student satisfaction than the use of a one-size-fits-all model. It also allows focused spending and effort in areas where positive benefits to students and universities are most likely to manifest [37].

Our third and largest challenge is around sustaining the URE experience in the undergraduate laboratories. Although this mechanism of providing undergraduate research is less time and money intensive than the provision of individual internships, it still has significant resourcing issues. This single implementation of ALLURE for 60 students cost approximately AU$16,000 ($10,000 in technical support fees, $3,000 in equipment, $2,000 in project development costs, and $1,000 in materials). The materials and equipment will remain as ongoing supplies and the project materials (e.g., laboratory manual and tutor notes) can be used in the future. The technical support component, however, will be an annual cost and this is unsustainable in the absence of external grant funding (which we are pursuing). Our specialist tutor (JBYHB) has also completed his PhD and moved on to postdoctoral studies—this leaves a personnel gap that cannot be reliably filled with willing, qualified PhD students on a yearly basis (the faculty associated with the course do not have time/expertise to teach the ALLURE project personally during semester). In the next iteration of ALLURE, we will have to address these issues. Although they did not seem like major stumbling blocks at the time of project inception, they are now a reality. In the absence of new grant funding, we will be forced to adopt a simpler ALLURE project, which (i) may not be on the same subject as this year and (ii) may be more in the course convener's area of expertise (convener is author SLR) to facilitate tutor supervision and project troubleshooting.

In summary, we suggest three major recommendations for academics who are attempting to implement an authentic URE alongside a more traditional laboratory in an undergraduate science course.

  • 1Build equity into the streams (in terms of invested student time, skills acquisition, and assessment methods). Both choices need to be palatable and equivalent.
  • 2Allow informed self-streaming, rather than assigning students to a stream. Students differ in their needs, confidence, and motivations; this should be respected.
  • 3Consider how a URE will be resourced in subsequent years. Is the project sustainable in terms of personnel, expertise, time, and funds? If not, consider ways to improve sustainability.

We close with a comment made by ALLURE Student 6 who described ALLURE as “Very stressful, but worth it.” We understand, and empathize with, the student's feeling. Implementing parallel LEAPS and ALLURE streams is stressful, but it also appears to be valuable. The evidence presented here suggests that a bifurcated laboratory stream is a viable mechanism for providing challenge for more motivated students, while maintaining a similar overall increase in skills for students in the two streams. Although the education literature suggests that the activities the students completed in the ALLURE stream are more pedagogically ideal than the LEAPS activities, we should keep in mind that not all students are the same. For some students, the LEAPS stream, which is a simpler and more “controlled” laboratory experience, still provides ample opportunity to access their zone of proximal development [38]; other students benefit from more freedom, and a requirement that they work at a higher cognitive level on a consistent basis.

We suggest that, where possible, students should be given the option of choosing a laboratory situation that best suits their academic background, career goals, and personality. This kind of “customized” education for a mixed-learner cohort does not have to yield stream-ordained educational inequity. If it is handled sensitively, and the activities are designed for equivalence, it can foster positive affect and similar skill gains for a large group of very diverse students.

Acknowledgements

This study was granted Human Ethics approval (UQ application number 2011000132). We thank Chantal Bailey for statistical analysis of the data. Our thanks are also due to Francesca Toselli who provided some assistance with ALLURE sample preparation, as well as the LEAPS technical staff (Jonathan Lloyd and Cath Covacin). We are grateful to Ulrike Kappler and Bernie Carroll who provided protocols for the experiments that eventually became the LEAPS series. Funding for this project was generously provided by the University of Queensland Strategic Teaching and Learning Grants Scheme.

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