I wouldn't say that he's right to send her home, especially since he doesn't know anything about her family situation. If she's in a normal home and just throwing a tantrum, she might be worrying her parents and that'd be bad, but if she's in an abusive home, he has no idea what kind of trauma she might be subjected to after she goes home, so I think the safer bet would be to talk it out with her properly and find out what's going on.