It takes a pretty special athlete to consistently catch a punt. Returners, and punt returners specifically, have to possess the ability to block out of their mind that there are 10 hungry defenders sprinting downfield just yards away just itching to lay the biggest hit of their lives on you.
At Penn State, when players are returning kicks, special teams coordinator and running backs coach Charles Huff is loaded with different distraction drills to train his returners to block out everything but catching the ball.
Huff will toss tennis balls at them while they try to focus on catching the kick, he'll throw boxing gloves on them to make sure they're catching the ball with their elbows pinned to their sides, and he'll also get a giant exercise ball out.
All these things are probably laying around your house (or around the school) anyway, so why not take a page from coach Huff and bring them out to the practice field to make your returners better.