This microethnographic study investigated the use of textbooks in six high school biology teachers' classrooms. Purposeful sampling techniques identified three textbook-centered (TC) teachers and three multiple-reference (MR) teachers. Composite profiles of TC and MR teachers and their classroom environments were constructed using data collected during classroom observations. The data were categorized and analyzed using the Project Synthesis “desired state” and “actual state” categories and descriptors as a framework (Harms & Yager, 1981). Thus, this study sought to ascertain if the nature of teachers' textbook use reveals relationships between factors indicative of the biology education “desired state” or “actual state” criteria. TC biology classrooms aligned with the actual state criteria in over 95% of the data entries. MR biology classrooms aligned about equally with the actual state and desired state criteria. Regardless of textbook orientation, teachers did not utilize desired state criteria in the process of evaluating student performance. Factors other than textbook orientation appear to align with desired state criteria. Identified factors include (a) the curricular goals espoused by individual teachers, (b) the instructional strategies used to implement the curriculum, and (c) the teacher's commitment to professional development. Preservice and in-service education must enhance teachers' ability to formulate goals consistent with desired state criteria in science education, develop appropriate strategies to implement those goals, and understand the need for continuing professional development.