The authors explored the impact of an online tutoring program, Math Whizz (Whizz Education, 2014), on student mathematics achievement at 15 elementary schools. Students participated in the use of the Math Whizz program for the duration of the school year as a supplement to mathematics instruction. The Math Whizz program recorded such information as initial mathematics age, growth in mathematics age, amount of usage, average quiz score, and average test score. Teachers were also surveyed regarding the implementation of the online tutoring platform. In addition, 1 school provided assessment scores from the summative statewide mathematics assessment, which was used as the outcome variable of a multiple regression with variables from the online tutoring program as independent variables. Findings indicated that Math Whizz usage was related to improvement in mathematics achievement as measured by the online tutoring program, teacher survey responses, and the state assessment data.