The Classroom Behavior Description (CBD)--a brief 10-item checklist on which teachers rate preschool childrens' behaviors which are considered most likely to influence school performance--was developed on the basis of earlier extensive research with more comprehensive children's behavior inventories. Results are reported of studies of teachers' ratings of 360 children, ages 2 to 6, in Head Start, Right-to-Read, day care programs, and in a school for mentally retarded youth. Impressive correlations were obtained between CBD ratings, cognitive measures, and other behavior ratings. Five years later, CBD ratings of a sample of Head Start children correlated reasonably well with third grade mental ability test and achievement test scores, and with placement in special remedial classes. Results should be of interest to preschool educators seeking a simple and inexpensive method to help identify children who can profit from early prescriptive intervention to improve cognitive development and scholastic achievement. (Author/GDC)