The consideration of threshold concepts is offered in the context of biological education as a theoretical framework that may have utility in the teaching and learning of biology at all levels. Threshold concepts may provide a mechanism to explain the observed punctuated nature of conceptual change. This perspective raises the profile of periods…

Interviews 9th and 10th grade students (n=13) who studied an ecology unit and analyzed tape-recorded data for changes in organization of knowledge, represented by ideational networks and the development of higher cognitive operations. Provides insights into how students developed knowledge schemata, ideational networks, and the capacity to express…

Considers effective dialogue between teacher and student essential for promoting meaningful learning in the classroom. Effective dialogue enables teachers and students to be active in the construction of shared understanding by making explicit the overlap between the perspectives held by students and teachers. Suggests that concept maps provide a…

Reviews five methods of representing cognitive structures: (1) free word association; (2) controlled word association; (3) tree construction; (4) concept map; and (5) flow map. Discusses the applications as well as the limitations of these methods by comparing the types of analysis that are generated. (Contains 37 references.) (Author/YDS)

Explores the knowledge development of Taiwanese 5th grade students (N=28) of biological reproduction. Proposes three stages of knowledge acquisition based on the results of the study. (Contains 17 references.) (DDR)

Reports research that examines children's models of seed. Explores the conceptions held by children (N=75) of germination and seed formation. Concludes that children hold a restricted meaning for the term 'seed'. (DDR)

Presents a study in which the conversations of primary school groups were collected in a botanical garden and analyzed for content. The data were examined for the effects of the presence or absence of an adult in the group, age, and the sex of the pupils. (Contains 27 references.) (Author/DDR)

Describes a multiple-choice instrument that reliably and validly diagnoses secondary students' understanding of photosynthesis and respiration in plants. Highlights the consistency of students' misconceptions across secondary levels and indicates a high percentage of students have misconceptions regarding plant physiology. (CW)

Described is a study of 147 students that indicated a high proportion of students did not understand the concept of limiting factors. Textbook presentations that create problems are discussed. Strategies which may be more effective in teaching the concept are suggested. (CW)

Examined are some of the distinctive features of the biological sciences. Discussed are the use of models with case studies, universal principles, and alternative frameworks. (CW)