摘要:This study compared teacher perceptions about state-mandated biology end-of-course examinations in North Carolina and Texas. Heuristic inquiries, of five Texas and nine North Carolina high school biology teachers were conducted over two years. Data were collected by audio-recorded interviews, discussions, personal journals, observations and open-ended questionnaires. Results indicate that biology courses with end-of-course testing; 1) cover too many topics, 2) move at a rapid pace that is determined by the number of topics rather than student understanding, 3) replace biology curriculum instructional time with practice tests and other test preparation activities, 4) diminish emphasis on laboratory and field investigations and 5) are not based on scientific inquiry or student interests in biology. Our study is significant in three ways. First, it provides information through teacher perceptions about the influence of end-of-course examinations on curriculum and instruction. Secondly, it is unique in that it examines the influence of these examinations through case-study analyses conducted by researchers who were also practicing high school biology teachers. Thirdly, it is unique in that it compares the perceptions of biology teachers concerning end-of-course testing in North Carolina and Texas, states with the longest history of end-of-course testing.