Most college students are still dependent on their parents, so in fact they're not fully adults. To me, you're finally an adult when you make your own way in the world. For too many college students, their college experience is just several more years of prolonged adolescence in an artifical environment. If you notice, most of the students who're working to pay their way through college are far less likely to cut class or to goof off. You value what you earn far more than what you're given.

Take a look at those young people who enter the workforce out of high school, including going into the military. Quite often, you'll find them more mature than their college student counterparts. Being responsible for yourself by working for a living, paying your own bills, picking up after yourself, and all of the other things tends to expose the world for how it is rather than how you wish it to be.

I remember when the voting age was reduced from 21 to 18. It was in the latter days of the Vietnam war. The argument was that if someone is old enough to be drafted and to risk his life for his country, then he's old enough to vote. It's an emotional argument with some merit.