Most pups munch on anything when they are teething, but some of them take up a habit of biting people's legs and/or tugging their pants. I hear it's also called "herding" because that's how a dog herds the sheep and it's very common in breeds that have an ancestry from sheep dogs. My dogs don't do that, mainly because I eye or grumble at them menacingly if they bite at me on purpose, to make them realise that it's not a game. It's primeval of me, but it works well to break the habit, as they stop permanently after two or three times. I've seen dogs that persist though. How do you deal with this?