An experimental study on CAS in a core calculus course found:
-- The experimental group attained a higher mean score than the control group on thirteen of twenty items.
-- Among the twenty items, the only significant differences in mean scores (p < 0.05) were found in eight of the items favoring the experimental group.

Connors, M. A. and K. G. Snook  (2001). "The Effects of Hand-Held CAS on Student Achievement in a First Year College Core Calculus Sequence." The International Journal of Computer Algebra in Mathematics Education 8(2): 99-114.

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