A quasi-experimental design in six kindergarten classrooms (n = 123 students) was used to study the effects of the KinderTEK iPad-based math program on the math achievement of students in general education classrooms. Student math outcomes in three treatment ("early start") classrooms were compared to math outcomes for students in three comparison ("late start") classrooms. Results suggested that relatively brief exposure to KinderTEK produced gains on distal measures of early numeracy and that, on average, timing of intervention delivery did not impact end of year math outcomes. However, exploratory analyses suggested that earlier and longer use of KinderTEK may have provided a benefit for students most at risk in math. The utility of quasi-experimental studies within an overarching research program and implications for the adoption of technology-based math programs in kindergarten classrooms are discussed. [This paper will be published in "Journal of Special Education Technology."]