The I CAN Learn[R] Education System is an interactive, self-paced, mastery-based software system that includes the I CAN Learn[R] Fundamentals of Math (5th-6th grade math) curriculum, the I CAN Learn[R] Pre-Algebra curriculum, and the I CAN Learn[R] Algebra curriculum. College algebra credit is also available to students in participating schools through the 121 lesson CLEP program, an open enrollment dual-credit program for middle and high school students. Studies included in this What Works Clearinghouse (WWC) review assess the effectiveness of the Pre-Algebra and Algebra components of the I CAN Learn[R] Education System. The WWC reviewed 27 studies on I CAN Learn[R] Pre-Algebra and Algebra. One of these studies meets WWC evidence standards; four studies meet WWC evidence standards with reservations; the remaining 22 studies do not meet either WWC evidence standards or eligibility screens. Based on the five studies, the WWC found positive effects in math achievement. The conclusions presented in this report may change as new research emerges. Six appendixes are included: (1) Study Characteristics; (2) Outcome Measures; (3) Summary of Study Findings; (4) Summary of Subgroup Findings; (5) Ratings; and (6) Extent of Evidence. (Contains 9 footnotes.)