The purpose of this report is to describe the results of a series of studies conducted on the relationships between census information and school achievement in the Chicago Public Schools. These studies were designed as an exploratory investigation to determine the extent to which grade-level achievement averages could be predicted using data from the third count (block statistics) and fourth count (tract statistics) of the 1970 Census, without including data on race or ethnicity. In particular, one of the original purposes was to determine whether evidence could be found of a differential effect on school achievement associated with concentrated urban poverty. The results of the study suggest that differences in achievement among the schools in the sample are associated with differentials in the concentration of poverty and poverty-related characteristics. Stated differently, whether poverty and its correlates are relatively concentrated (or absent) in the urban neighborhoods in the sample is related to the degree to which achievement scores in local schools are unexpectedly different than would be predicted on the basis of a linear relationship between poverty and achievement. (Author/JM)