from memory rps in elwood for starboards.
if kids are coming on board, then the bigger the better.... also for kids consider a board that has a grip from nose to tail,, and rail save tape to stop the paddle chipping the board.
if available try a demo board.
it's really easy with the correct gear, just get a few simple guidlines and you'll be supping in no time.
DO IT, you'll love it and so will your kids.