Key points are not available for this paper at this time.
Doris R. Entwisle, Karl L. Alexander, Summer Setback: Race, Poverty, School Composition, and Mathematics Achievement in the First Two Years of School, American Sociological Review, Vol. 57, No. 1 (Feb., 1992), pp. 72-84
Entwisle et al. (Sat,) studied this question.