Anonymous wrote:Second Beast Academy. It's great, and from what I've been able to ascertain, it's good for those kids who really get math (not just teaching memorize and drill but actual underlying concepts and critical thinking)
Have you also considered non-math enrinchment? Honestly, I can't recommend Cub Scouts enough - one extra curricular activity which gets you exposure to a whole lot of different things, including STEM content, leadership/communications, service, outdoor skills/camping, etc.
Cub Scouts is great for a lot of reasons. It does have an entire NOVA award that kids can work on that is STEM based. When kids are in fifth grade they can move to a Scout Troop. There are some great STEM based Merit Badge options. And if your are on the NOVA area you can look up STEM Scouts. It is a STEM based program that is only offered in the National Capital Area Council.