As he's developing his theories of how to educate his ideal philosopher-kings, Socrates has realized he has a problem. If you take people who have been taught certain things are just and right all their lives, and then lead them to question those things (as part of the process of leading them to a truer understanding of ultimate truth and justice), they are liable to give up attempts at finding truth altogether and just go out and party.
Hence, the college/university and all the problems that have been associated with it for, oh, the last several hundred years. Take people at the stage of life when their passions run the highest and their judgment runs the lowest, remove them from the influence of their family and community, and cause them to question everything they have been taught. What would you expect to happen?
Most institutions of higher learning have taken one of two approaches: crack down with strict rules and Gestapo-like enforcement; or ignore it and hope nobody dies. Actually, there's generally at least some of both, and neither of them really works.
Socrates decides to do something else altogether. He just won't let anyone study philosophy until they are thirty, have worked for awhile, and are a bit more sane.
The idea certainly has its merits, but, alas, we don't live in a communal paradise and there is no one to watch the kids and pay the bills while more mature people ponder the Great Ideas. There is some hope, though, that with improvements in communication and distance learning, we can integrate higher education with real life in a more productive way.
In the meantime, should I put Plato aside for the next four years?