This study examines the effects of using Texas Instruments' Voyage 200 calculator (V200), a graphing calculator with a built-in computer algebra system (CAS), on attitudes towards CAS and achievement in mathematics of junior college students (17 year olds). Students' attitudes towards CAS were examined using a 40-item Likert-type instrument developed by the main author while the effects of the use of CAS on student achievement were examined by comparing scores of the treatment and control groups on an achievement test designed to reflect the curricular goals. Descriptive data were also collected to investigate students' perceptions of the usefulness of the V200. Although a significant positive difference in student achievement was not found between the treatment and control groups, the results of this study indicate that appropriate use of the V200 in the mathematics classroom can improve students' attitudes towards CAS. (Contains 6 tables and 8 figures.)