If a 13 year old growing boy is 5 feet three inches and 103 lbs. What size board would he get? Thanks!

A pretty general way to find the height of the board is having a board about the height of the lips. You could prolly push it a few CM too since he's still growing. Here's a more detailed chart from TheHouse.com: <BR><img src="http://www.wakeworld.com/MB/Discus/messages/11975/753452.jpg" alt="Upload"> <BR> <BR>Hope that helps a little bit.