Thanks for posting, everyone. Here's my take:

I think 5 is too young to start going all day every day. Although I don't see a problem with a 5-year-old being involved in a group learning situation a couple of days a week. I think 10 is too late. I would begin school at 5, but not go every day at first. Maybe start going everyday at around 8 or 9. Something like that.

The first few years should be spent learning arithmetic and reading/writing. That's it. Those are the building blocks upon which subsequent learning is built. And I would begin with rote memorization, but start introducing "discovery-based" learing pretty quickly a little at a time. Then beginning around 10 or 12, start introducing history and science. And these need to be taught way better than what they are now. We should not be teaching scientific theories as facts to memorize like we do now. We should be presenting the children with evidence and suggesting the theories that we now believe best explain the data. That's how science works, and if you're going to teach science then you should teach it right. I also think foreign language should be mandatory and should be taught from the beginning (studies clearly show that language acquisition is way better if you start before the age of 10).

I would end high school at the age of 16. Then you could have 2 years of liberal arts education for those who choose to continue (this would basically run about like a community college). Then we could completely remove the liberal arts portion of university so that if you go to college you only take courses in your major. Thus reducing the amount of time it takes someone to become reasonably educated. If you want a blue-collar job, then go get one when you're 16. Why not?