One of my sons (Patrick, the one who’s weirder than all the other weird sons) completed five grades of math in a year on Khan Academy. Now (just turned 15) he’s doing Algebra II, Pre-Calculus, and Linear Algebra, as well as three programming languages.
Just call him Sheldon ...
Bravo, big boy! Khan is awesome. We are loving Life of Fred. How can anyone not? Hard bound math books by a mathematician from first grade through college. Filled with funny stories and relevant life lessons. Ever used it?
All my little ones used the wonderful Miquon workbooks early on. Math books SHOULD BE MADE BY MATH GENIUSES. Too bad none of the school ones ever are.