How did God punish 42 little chidren for making fun of Elisha's bald head?

By sending two bears to rip them apart

As he was going up by the way, there came forth little children out of the city, and mocked him, and said unto him, Go up, thou bald head; go up, thou bald head.

And he turned back, and looked on them, and cursed them in the name of the LORD. And there came forth two she bears out of the wood, and tare forty and two children of them. 2 Kings 2:23-24