yeah barefoot is ok in a laser, but if he was doin 420's his feet would die.
I coach, and kids are required to atleast have sandles, I recomend Wakeskate shoes, just cuz the sailing shoes that do the same thing as wakeskate shoes look pretty gay, as for pants, just wear shorts there, and bring a swim suit, so if you do go out on the water, you can change in the bath room. Also a lifejacket is a must too, many classes requier them.
Here are a few websites to check out for shoes too.
Reef Byerly 2's (What i use)
http://www.boardstop.com/product_info.php?cPath=45_47&products_id=1454&ref=2
More Shoes
http://www.boardstop.com/index.php?cPath=45_47
Anything that has Mesh in the name from DVS are good choices too