Two studies involving 242 college students are described. First, a 15-item test on means was given, identifying students' misconceptions. In the experiment that followed, most students were able to acquire the appropriate schema of statistical concepts by engaging in diagnostic activities embedded in a feedback-corrective procedure. (MNS)

A test of logic using implicational and disjunctive sentences was given to Chinese and English speakers. No differences were found on "if-then" sentences, but differences were found on "or" sentences. (MNS)

The literature on proportional reasoning is reviewed. After methodology is discussed, strategies used to solve proportion problems, variables that influence performance, and training studies are each considered. (MNS)

Describes observations, written samples, and interviews of (n=24) high school teachers learning concepts of group, subgroup, coset, normality, and quotient group in an Abstract Algebra course. General observations are made about the role of errors and misconceptions in light of an action-process-schema framework. (32 references) (MKR)