Well in my opinion every league should have a standard rule saying no athlete can be drafted right out of High-school (I believe only the NBA allows this, Correct me if I'm wrong), and that a player should have to go to College for at least 2 years (In American Sports). But that wasn't the question.
NBA no longer allows this. You need at least one year out before you can play there. Which doesn't really help the issue, as a lot of guys just go to college for one year and leave, never intending on getting a degree.
Baseball players can get drafted out of high school, but I believe if they don't sign they have to stay in school for at least 3 years or something?
Football players need to stay in school for 3 years before going pro.
The way I look at it, if an athlete wants to go pro right out of high school and they're good enough, they should be allowed to. Who's to tell them they have to wait to make millions of dollars a year? Like I said, most of them don't even bother going for the degree anyway, that's why you see all the NCAA rules violations.
They can always wait till later to go back to college, plenty of NBA guys do this over the summer. Remember Vince Carter? A lot of guys will get oppurtunites to stay in the sport through coaching, scouting, a TV job, etc.
Obviously an education is important, but if you were a super talented high school athlete, wouldn't you want to make as much money as you could while it's there and then learn about the other stuff later? I know I would.