The 5-stage model of Ross was used to examine the role of instruction in facilitating children's acquisition of place value knowledge. Compares children from 2 samples on 10 tasks designed to reveal their thinking about place value. Discusses implications for theory and classroom. (YP)

Reports on a study designed to document that learning-disabled (LD) students make errors in estimating the passage of short time durations, and to determine if LD students were different than nondisabled in time estimation. Non-LD and LD students differed significantly in estimations of 15-second intervals, but not 3-second intervals. (PK)

Reports on research designed to systematically examine how the use of personalized word problems as practice examples would affect learning and attitudes. A computer program was used to generate the problems. It was concluded that presenting problems in familiar contexts made materials more interesting and understandable for students. (PK)

A sampling of teachers (n=348) and principals (n=31) responded to a questionnaire designed to assess their beliefs about the effects of, experiences with, and impediments to calculator usage in elementary school mathematics. Results indicated that teachers expressed concern regarding negative effects of extensive calculator usage on mathematical…