The purpose of this investigation was to determine the extent to which multicultural science education, including indigenous knowledge representations, had been infused within the content of high school biology textbooks. The study evaluated the textbook as an instructional tool and framework for multicultural science education instruction by comparing the mainstream content to indigenous knowledge perspectives portrayed in the student and teacher editions of 34 textbooks adopted in Florida within the last four adoption cycles occurring from 1990 to 2006. The investigation involved a content analysis framed from a mixed methods approach. Emphasis was placed, in consideration of the research questions and practicality of interpreting text with the potential for multiple meanings, within qualitative methods. The investigation incorporated five strategies to assess the extent of multicultural content: 1) calculation of frequency of indigenous representations through the use of a tally; 2) assessment of content in the teacher editions by coding the degree of incorporation of multicultural content; 3) development of an archaeology of statements to determine the ways in which indigenous representations were incorporated into the content; 4) use of the Evaluation Coefficient Analysis (ECO) to determine extent of multicultural terminologies within content; and 5) analysis of visuals and illustrations to gauge percentages of depictions of minority groups. Results indicated no solid trend in an increase of inclusion of multicultural content over the last four adoption cycles. Efforts at most reduced the inclusion of indigenous representations and other multicultural content to the level of the teacher edition distributed among the teacher-interleafed pages or as annotations in the margins. Degree of support of multicultural content to the specific goals and objectives remained limited across all four of the adoption cycles represented in the study. Emphasis on standardized testing appeared in the six textbooks representing the most recent adoption cycle. Recommendations included increased efforts to identify quality of content by including input from scholars in the field of multicultural education as well as indigenous peoples in the creation of textbook content. Recommendations also included further clarification of the definition of science within multicultural science education frameworks, indigenous knowledge as compared to Western science and pseudoscience, and scientific literacy as a central focus to a multicultural science education meant to address the needs of an increasingly diverse student population and prime-age workforce.