What mathematics programs have been proven to help middle and high school students to succeed? To find out, this review summarizes evidence on three types of programs designed to improve the mathematics achievement of students in grades 6-12: (1) Mathematics Curricula (MC), such as The "University of Chicago School Mathematics Project," "Connected Mathematics," "Saxon Math," and other standard and alternative textbooks; (2) Computer-Assisted Instruction (CAI), such as "I Can Learn," "Jostens/Compass Learning," and "Accelerated Math"; and (3) Instructional Process Programs (IP), such as cooperative learning, mastery learning, and other approaches primarily intended to change teachers' instructional strategies rather than curriculum or technology. Overall, 102 studies met the inclusion criterion, of which 28 used random assignment to treatments. These included 40 studies of mathematics curricula, 40 studies of CAI, and 22 studies of instructional process programs. [For the full report, "Effective Programs in Middle and High School Mathematics: A Best-Evidence Synthesis. Version 1.4," see ED527635.]