The relationship of attitudes toward mathematics to mathematics performance, gender, mathematics course-taking plans, and career interests were investigated. Students enrolled in public middle and high school mathematics courses (722 male, 794 female) served as subjects. The Fennema-Sherman Math Attitude scales were used to measure attitudes toward mathematics, a background/future plans questionnaire was administered to assess course-taking plans and career interest, and final mathematics course grade was used as a measure of mathematics performance. Results showed that attitudes toward mathematics were predictive of final mathematics course grade and the intention to continue to participate in mathematics courses once enrollment becomes optional. Attitudes also discriminated among students with different career interests. Students in more accelerated mathematics "tracks" had more positive attitudes, greater intention of taking optional mathematics classes, and were interested in more mathematically-related careers. Males and females were equally likely to express plans to take mathematics courses once participation became optional. Overall, females' attitudes were more positive than expected. However, their lack of confidence in their abilities to learn mathematics and their higher levels of mathematics anxiety, coupled with a lack of interest in more mathematically-related careers, suggest that important gender differences still exist. (Author)