Two ethnic groups of students, majority and minority, were compared on variables of a Psychological Productivity Model. Black and Hispanic students were grouped as minorities, and White students were considered majority students. Participants were 120 high school students from an urban high school in the Southwest. The Psychological Productivity Model entailed seven variables (home, social environment, time on task, motivation, quality of instruction, peer group, and media). Sex differences on the variables were also examined. Descriptive statistics and seven separate two-way analyses of variance were performed on the data. The variables Ethnicity and Sex both showed significant main effects on the variable Motivation, favoring the majority ethnic group and males, respectively. The results, however, fail to reveal any significant interactions. No significant main effects for the variables Ethnicity and Sex were found on the remaining six dependent variables. The results of the study reflect the need for further and more intensive, in-depth research on ethnic and sex differences on motivation. Results have implications for curriculum design. Five tables present study findings. (Contains 24 references.) (SLD)