This article describes the results of work being conducted on the development of a model for student achievement. Steps employed in the reduction of the large number of variables into a fewer number of indices and the utilization of these indices in regression analyses are described. Some of the more salient findings are that both school achievement and school resources (including such things as the number of pupils per teacher, the teacher's view of his working conditions and the school's special staff and services) are highly related to the socio-economic status and racial-ethnic composition of the student body. The influence of the schools is bound up with the kinds of students that they get initially. Consequently, when the schools are equated for the kinds of students that they get they tend also to be equated for the influence that they have on these students. The schools play an important role in promoting student achievement and the extent of this involvement appears to be greater for higher socio-economic status and white students than for lower socio-economic status and non-white students. © 1969.