In an early education program, 100 disadvantaged 4-year-olds (50 Negroes and 50 whites) attend classes one-half day, four days a week, from October through June. A teacher visits each child's home every other week to conduct a tutorial session lasting 1 1/2 hours. Three objectives of the program are (1) to develop a preschool curriculum based on…

This paper examines sixth-grade children's thinking related to solving ratio and proportion problems before these children had received any instruction in the domain. It explores unitizing and norming, one of the processes identified by both content analyses (Behr, Harel, Post, & Lesh, 1990); Harel, Behr, Post & Lesh, 1990) and research in…