The Good and the Beautiful is a nondenominational Christian curriculum with free K-8 language arts and math PDFs. See how it works, what parents like, common cautions, and where to buy.
Beast Academy is a challenging, comic-style elementary math curriculum from Art of Problem Solving. See how it works, what parents like, common cautions, and where to buy.
Teaching Textbooks is a self-teaching math app for Math 3 through Pre-Calculus that teaches, grades, and explains every problem. See how it works, what parents like, and common cautions.
Math-U-See is a hands-on, mastery-based math curriculum from Demme Learning that uses manipulative blocks, video lessons, and workbooks from Primer through Calculus.