That's nuts! Even if the kid wants to do it, I still think it's nuts....at least at that age. I don't like any type of boxing. I don't understand why people enjoy watching two people clobbering each other.
A few weeks ago there was a big kerfuffel about a mother in New York letting her 11 year-old son find his way own home from Bloomingdale's. Some of the pople up in arms called it "abuse."
This seems to fit that label much better than the earlier case.