The purposes of the study to determine psychometric characteristics of the Series Learning Potential Test, the effects of Learning Potential training on Series scores, and the relationship of Series scores to IQ, race, social class, and reading achievement. The Series Test was administered to students in 79 classrooms in five Connecticut towns which differed in racial and socioeconomic composition. The test was shown to be highly reliable, and the two forms were found to be statistically equivalent. Difficulty levels of several items indicated a ceiling effect reflected in total scores. Training was found to be effective with second and third graders from lower class towns and first and second graders in middle class towns. Series scores were positively related to IQ and reading scores, and students who were white or middle class attained higher Series scores. For these reasons, as well as the ceiling effect, the Series test appears to be less useful than other tests as a measure of Learning Potential. (Author)