Originally Posted by Blackroady
Seriously - anyone with a brain ( ie Meme etc ) will be sensible , however you do see & experiance no end of very young children in control of boats that are very powerful .
"In control" is different than "in command".
A supervised child is one thing (for instance, I've let my dive buddy's 4 year old steer the boat and control the throttle while I'm holding him on the seat; he usually heads for the nearest large boat...), but I wouldn't necessarily toss him the key and let him take off on his own.
In California, I believe you have to be 16 to operate (be in command of) a power boat in excess of 15hp. Don't know about other states or countries.