It takes a long time to teach our kids because the system we have for teaching them is horribly inefficient and has been for thousands of years at this point.
But it carries on not because it's good but instead because it is so indoctrinated and there is no allowance to try anything radically different. If you try even things like "new math" parents freak out because that's not what they learned.
In fact, the entire schooling process we have, from primary schools to colleges and post-graduate should be reexamined at every level. Does it make sense to do it this way, or are we doing it this way, effectively spending a third of someone's life on school, only because the system is dedicated to this method?
Basically, the concepts of college as we know them are at least several hundred years old. Virtually every area of science and medicine and life itself has changed over that time, however we still teach basically the same way. This doesn't make any sense. That process should have changed and evolved like all the others but it largely hasn't. This should be questioned by anyone -are we doing this the right way? Does it make sense? Or is there a better way?
However everybody currently on the loose was educated that way so they have no incentive to change it for new kids, and of course the educators themselves have little or no incentive to reinvent how they do what they do, and even the parents have no incentive to let their child try a new way that may jeopardize the child's accomplishments compared to other kids -nobody wants their kid to be the first one to never actually have a diploma for something, for example.
Spending a third of someone's life on schooling years is on the face of it ridiculous. But I don't think this can possibly change. And that's too bad.