"Everyday Mathematics"[R], published by Wright Group/McGraw-Hill, is a core curriculum for students in prekindergarten through grade 6. At each grade level, the "Everyday Mathematics"[R] curriculum provides students with multiple opportunities to learn concepts and practice skills. Across grade levels, concepts are reviewed and extended in varying instructional contexts. The distinguishing features of "Everyday Mathematics"[R] are its focus on real-life problem solving, student communication of mathematical thinking, and appropriate use of technology. This curriculum also emphasizes balancing different types of instruction (including collaborative learning), using various methods for skills practice, and fostering parent involvement in student learning. The What Works Clearinghouse (WWC) reviewed 72 studies on "Everyday Mathematics"[R] for elementary students. One of these studies meets WWC evidence standards with reservations; the remaining 71 studies do not meet either WWC evidence standards or eligibility screens. Based on this study, the WWC found potentially positive effects in math achievement for elementary students. The conclusions presented in this report may change as new research emerges. Appendices include: (1) Study characteristics: Waite, 2000; (2) Outcome measure for the math achievement domain; (3) Summary of study findings included in the rating for the math achievement domain; (4) Summary of subtest findings for the math achievement domain; (5) "Everyday Mathematics"[R] rating for the math achievement domain; and (6) Extent of evidence by domain. (Contains 10 footnotes.)