dented bumper

hey all its me again this time i need to know how all you body guys would go about getting dents out of a bumper. the back bumper on my scamp has a couple and i cant afford a new one so im wondering what to do. i tried smacking them out with a BFH and a piece wood but just ended up breaking the wood.....:banghead:

so come on guys im open to suggestions what should i do?

you can kinda see them in the pic.