Prevalence of blood circulation misconceptions among prospective elementary teachers.

Research shows that misconceptions about human blood circulation and gas exchange persist across grade levels. The purpose of this study was twofold: 1) to investigate the prevalence and persistence of blood circulation misconceptions among prospective elementary teachers and 2) to evaluate the effectiveness of learning activities for discovering what students know and can explain about blood circulation and lung function. The context was an undergraduate introduction to biology course taught by two professors across three semesters at a state university. Independent reviewers identified five categories of erroneous ideas about blood circulation. Many categories still presented problems to students at the end of the course: 70% of prospective elementary teachers did not understand the dual blood circulation pathway, 33% were confused about blood vessels, 55% had wrong ideas about gas exchange, 19% had trouble with gas transport and utilization, and 20% did not understand lung function. Results show that an interview about a drawing as a final exam was significantly better at revealing different errors and a higher frequency of erroneous ideas compared with an essay exam. There is an urgent need for instructional tools to help undergraduate students realize the discrepancies between their own ideas about blood circulation and those of the scientific community.