I wish i had a dad that was interested in RC and could afford to get me started. My interest started at age 9 or so when i got a esta rocket kit and had to go the the hobby shop to pick up some engines, i saw all the RC planes and was hooked (I still contribute that day as being the resin I'm studying aerospace engineering). Never got into the sport untill i came to Mississippi state and joined the RC club, now i have 2 planes and loving every moment of it.

The moral of this, same as above start them when they express interest.