There is a broad consensus across the political spectrum on the need for K-12 education reform. The Obama administration focused on early childhood programs, common standards, charter schools, and more effective teachers. As school districts align curriculum and teaching practices with common core standards, standards-based mathematics programs are replacing traditional curriculum. The purpose of this study was to examine different types of curricula used to teach mathematics and its impact on student academic achievement. This research study analyzed the results of the 2013 Fourth Grade Mathematics, National Assessment of Educational Progress (NAEP). Variables were developed from responses to school surveys that are part of this dataset. Variables used were the school reported use of curriculum in the classroom. The participants in this study consist of fourth grade mathematics students across the United States, including English Language Learners (Ells), both male and female, attending public and private schools. The research design of this study was a non-experimental cross-sectional explanatory design (Johnson, 2001) that used a multiple regression analysis to measure the relationship of the predictive variables (commercially designed math curriculum, math curriculum structured by teacher discretion, math curriculum structured by state standards, math curriculum structured by district standards) and the dependent variable of student achievement on the 2013 NAEP mathematics assessment in 4th grade. A multiple regression analysis was conducted to explore the relationship between fourth grade, 2013 NAEP mathematics test scores and four different types of mathematics curricula. The selection of curriculum materials was an important undertaking. The significance of this study is to provide information concerning the effects of curricula on student mathematics achievement. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]