Yes, it's still done several times a day. Your son will probably get a kick out of it. Get there about 5-10 minutes beforehand. Get in the front row. Have him obey Merlin's directions (particularly his "invisible rope"). He asks for volunteers, have him raise his hand, smile, and be polite. Don't jump up and down and shout "Pick ME!!!" That wouldn't guarantee anything, but from our observations it'll increase his odds.