Better to let them live as they would like and learn math only if they would like.

If your kids were really gifted or really inclined to learn it, you wouldn't need to research it yourself.

Around that age 10-12 they generally can use the internet and already have their own interests, and are smart enough to Google it and build stuff by themselves.

If you keep getting that much involved in their lives they will have development issues. You only get involved if they are really slow and get a professional to help.