Elements of instructional design such as explicitly stated objectives, reviews, examples, questions, and feedback were incorporated into the laboratory manual and instruction for a unit on kinetics in a college laboratory course. This treatment (high structure) was given to five sections of students (N = 109), while a laboratory manual and instructions that emphasized informational content without the use of these design strategies (low structure) was given to another five sections (N = 108) taught by the same instructors. The students receiving the additional structure scored significantly higher on a quiz, took less time to solve a set of laboratory problems, and felt more satisfied with the instruction provided. There were no differences between groups in their comfort with the knowledge acquired. There were no interactions with performance outcomes, but several occurred for attitudes, treatments, and personality measures. The more conforming the students, the more satisfied they were with the instruction in the high-structured group and the less they liked it in the low-structured group. The more motivated the students, the more they liked the instruction in the high-structure treatment, and even more in the low-structure group. There was also a complex interaction among treatment, anxiety, ability, and treatment satisfaction.