Educational Research Institute of America (ERIA) conducted a pretest-posttest study to assess the effectiveness of GO Math!, in Grades 2, 3, and 4 during the 2015-2016 school year. Study participants included 92 teachers and 2,200 students enrolled in 10 different schools in 4 states. Tests were developed to match the content of the GO Math! program used in the study as well as to emphasize the National Council of Teachers of Mathematics (NCTM®) Standards. The results indicated that across the three grades, mathematics student growth was statistically significant. In addition, the results showed that across all three grades, mathematics student growth for the high-achieving and low-achieving students was statistically significant.