This article presents results of a research study. Sixty-one first graders' responses to interview questions about negative integer values and order and directed magnitudes were examined to characterize the students' mental models. The models reveal that initially, students overrelied on various combinations of whole-number principles as…

Children (n=336) in grades 1-5 were interviewed individually using a Piagetian task to study development from additive to multiplicative thinking. Multiplicative thinking was found to appear early (in 45% of second graders) but to develop slowly (only 48% of fifth graders used consistently solid multiplicative thinking). (Author/MKR)

Interviews with 107 children, ages 4-7, about uncounted quantities, counted quantities, and numerical equations showed that the ability to predict changes to counted quantities increased with age. Only 7-year olds were able to use covariance and compensation in the purely numerical context of derived equations. (Author/MKR)

Interviews with (n=20) primary teachers, who had participated in inservice workshops on Cognitively Guided Instruction (CGI), revealed three patterns of CGI use--as mainstay, as supplement, and decreasingly--which seemed related to their beliefs about mathematics, learning, and CGI itself. (40 references) (MKR)

Analyzed were 19 preservice teachers' understanding of division in 3 contexts. The teachers' knowledge was generally fragmented, and each case of division was held as a separate bit of knowledge. (Author/YP)

Analyzed questionnaire responses of 152 prospective secondary mathematics teachers, 10 of whom were interviewed, to investigate their knowledge of the concept of function. Results indicated that many did not have a modern concept of function, a limitation that influenced their pedagogical approach. (Contains 45 references.) (MDH)