"Scott Foresman-Addison Wesley Elementary Mathematics" is a core mathematics curriculum for students in prekindergarten through grade 6. The program aims to improve students' understanding of key math concepts through problem-solving instruction, hands-on activities, and math problems that involve reading and writing. The curriculum focuses on problem-solving skills, assessments, and exercises tailored to students of different ability levels. According to its developer, "Scott Foresman-Addison Wesley Elementary Mathematics" is aligned to the National Council of Teachers of Mathematics (NCTM) standards for the elementary grades. The What Works Clearinghouse (WWC) identified 13 studies that investigated the effects of "Scott Foresman-Addison Wesley Elementary Mathematics" on the math performance of elementary school students. The WWC reviewed seven of these studies against group design evidence standards. Three studies (Agodini, Harris, Thomas, Murphy, & Gallagher, 2010; Resendez & Azin, 2006; Resendez & Manley, 2005) are randomized controlled trials that meet WWC evidence standards without reservations. These three studies are summarized in this report. Four studies do not meet WWC evidence standards. The remaining six studies do not meet WWC eligibility screens for review in this topic area. Appended are: (1) Research details for Agodini et al. (2010); (2) Research details for Resendez & Azin (2006); (3) Research details for Resendez & Manley (2005); (4) Outcome measures for the mathematics achievement domain; and (5) Findings included in the rating for the mathematics achievement domain. A glossary of terms is included. (Contains 6 tables and 9 endnotes.)