I would follow the lead of Chuck Feeney. http://www.youtube.com/watch?feature=player_detailpage&v=OMcjxe8slYI
If my kids were young and I died now, I'd not give it all to them when they turn 18, probably split it up into 3 intervals over a few decades.
I inherited some money when I was young and dumb. I did some good stuff with it but overall it just delayed having to "earn a buck", and having not had to support myself on my own prior to the money I didn't value it the same as I would have 5 years later. After having to work for someone else and find out what being an adult is all about. I was a landlord at 18, still have one of them.
But actually having to work for something put me into a much better path to a much better life I wouldn't have pursued otherwise.