Our daughter studied the Jumpstart ACT Math module. This is a serious 15 to 20 hour course, covering every category/concept from which questions are drawn on the ACT. The included workbook is perfect for engagment during the 45 minute (average) segments, and a great refresher prior to the next test (flashcards are created in the course of doing the workbook). Being able to do one session a day, or work at whatever pace you want, is a fantastic feature. Use of the online portal is intuitive and easy.
Though school exams interfered with our daughter's completing the 20 modules before her Dec. 10 ACT, she finished the first 10. We are convinced this played a significant part in increasing her math score by 7 points, and she will wrap up the other 10 math modules (plus the additional Jumpstart ACT prep materials we immediately ordered after this great result) before the Feb. 11 test. Could not recommend this product more. Completely worth the money.