Addressing high demand for developmental math instruction and low rates of successful completing of the developmental coursework, with cost and space constraints, has been an ongoing challenge for postsecondary institutions. With advances in online instructional technology, particularly those based on artificial intelligence, web-based instruction is increasingly considered as a way to alleviate these burdens. This is among one of the first efforts that uses a quasi-experimental design to compare the academic outcomes of students who take a developmental mathematics course in a blended setting that combines face-to-face instruction with an online intelligent tutorial system, ALEKS, to the academic outcomes of students who take the same course in a fully online setting. Results suggest that students receiving online-only instruction perform worse on the final exam and receive lower course grades. However, a cost-effectiveness analysis suggests that fully online instruction has both a lower cost per student enrolled and a lower cost per student passing the course.