Variables expected to be associated with academic achievement were examined in a sample (generally exceeding 2500) from eight secondary schools in Baymon Norte, Puerto Rico. Concern was whether variables associated with academic achievement differed by sex or by socioeconomic status (SES). Multivariate analyses of variance with three factors of achievement, sex, and SES were made. High achievers tended to have accepting mothers, parents low on Hostile Psychological Control, and low on autonomy; and were more geographically mobile, had fewer siblings, were more intelligent, obedient, conscientious, artistic, group-mined, placid, self-disciplined, responsible, anxious (preocupado), mature, and less excitable. High schieving girls were less authoritarian, dogmatic, and test anxious, and gave fewer false but socially desirable responses. Students whose academic achievements were consistent with their SES were more assertive, less bragging, happier, and more esthetically sensitive than those whose achievements were discrepant with their SES. Self concepts were higher for achievers, especially for low SES students in junior high schools, and for all students in high schools. Low achievers, especially boys, disliked school. High achieving boys and low achieving girls were more self sufficient, while low achieving boys and high achieving girls were more group dependent. (Author/RJ)