Okay so the oldest boy is 16, if I get up in the morning, will I get a note saying he went off to college? Or what happens?

Most likely yes. I have woken up and had 15 yr olds gone off to college.

The same picture notice that pops up when you have a new baby will show up, with a different picture of course.

It depends on how long you're gone, the child will leave to college at some point after he/she turns 18. Like knk mentioned, you'll see the notice pop up as soon as you return to the game if he/she leaves.

I think every 2 hours your peeps will age a year, so lets say 4 hours from now the child should definitely be 18 and could go off to college then.

The peeps age roughly 1 year every 4 hours. The way it actually works out in the game, it's more like 1 year every 3.42857 hours (but who's counting?). They age about 7 years every 24 hours.

Oh! Okay Thanks for the numbers LadyCFII, that'll be helpful with making sure I'm awake for some significant ages.

Thank you everyone, I just didn't want to miss out on the big event.