Extends prior theory and research by postulating the existence of an intermediate class of concepts called 'hypothetical'. Investigates the hypothesis that three kinds of scientific concepts exist by constructing and administering a test on concepts introduced in a college biology course. Supports the hypothesis that intellectual development…

Investigates the effect of cognitive style on the performance of college students on proportional reasoning tasks. Reports that students having proportional reasoning can be misled by the presence of field effects and that there was a significant correlation between the test of field independence and the items of proportional reasoning. (Author/YP)

Investigated was the relation between student ability to translate sentences into equations, equations into sentences, and student performance in formal operational reasoning, proportional reasoning, and introductory-level chemistry. Results indicate that students who lack formal operational skills may experience problems in the translation of…

Presented is a study in which students' intellectual reasoning development was evaluated following instruction that emphasized formal operations in a traditional lecture format. Results indicated that formal-operational students had significantly more success in the three reasoning areas than transitional students and transitional students had…