The biggest requirement is time and dedication. Then, there’s consistency and a program that you have to stick to. As they get older, you also need to understand well the knowledge you give to your children.

As an alternative, you can hire private teachers to teach different disciples, but their number will increase with time, which may become cost-prohibitive for many.

Yes, there’s also online education portals but I wouldn’t want my kids to spend all their time i studying in front of a screen.

So I think most parent simply aren’t ready to commit to this for so many years.