This study of eighth graders investigates the effects of Kindergarten attendance on (1) Basic Skills Test (BST) performance and (2) the incidence of grade retention (non-promotion). To accomplish the first purpose, over 64,000 eighth grade pupils in the public schools of Tennessee were administered the BST. On each answer sheet of the BST pupils were asked to indicate whether they had attended kindergarten or not and their scores on the BST's four sub-tests (mathematics, spelling, language, and reading) were collected. To accomplish the second purpose of this study, data were obtained from a separate research study. Subjects were believed to be comparable with respect to achievement in basic skills and to kindergarten attendance to the sample of the present study. Nearly 6,000 pupils in grades 5 to 8 were selected from 48 schools on the basis of their mathematic achievement scores. The results from the BST demonstrated that achievement of pupils with kindergarten background was superior to that of non-kindergarten pupils in mathematics, spelling, language and reading. The effect was greatest for mathematics and language, and less for reading and spelling. Results from the study of mathematics achievement revealed that the incidence of retention in grade is considerably less for pupils with kindergarten experience than pupils without it. (Author/MP)