The Classroom Activity Files and Day Care and Home Learning Activities Files contain approximately 900 learning activites each, and were designed to promote competencies in children at different developmental ages. Twelve Head Start, kindergarten and preschool programs participated in a field study to evaluate the usability, content, and age-appropriateness of the files. The Developmental Profile was used to measure physical, self-help, social, academic and communication development in 788 three-, four-, and five-year olds enrolled in the programs. Pre- and post-tests and teacher evaluation forms were used. A secondary purpose of the study was to determine whether changes occurred in program practices as a result of the files and field test. Children in preschool programs in which the files were a major source of curriculum made significant gains. The greatest gains were in the academic area, while the most effective utilization of files occured in classroom settings. Expected gains were not achieved by use of both sets of files in day care programs, nor from the use of home-based files in home settings. Staff interviews indicated that teachers became more oriented to the developmental needs of children and more conscious of the need for individual child assessment as a result of their field test participation. (Author/JAC)