Is martial art the answer to the problem that my son have?

Recently, my 13 y/o son got into a fight with a bully. He got punched in the face but he also kicked the other guy's groin (ouch!). Now he wants to pratice a martial art but he doesn't know which one. Any suggestions? I heard about Krav Maga but I can't find any places that teach teens that art in Montreal, Canada.