Yes, this is all over the news here. Said teacher was indeed fired, but the parent did not contact police, nor let her kid be examined for the record, so pursuing any assault charges may be out of the question. A civil suit is probably more likely, but they're not going to get much from an unemployed teacher or near-bankrupt school district. Granted, this was a special ed kid who apparently was in her class for being a trouble maker and, at that time, had been cruelly mocking a mentally disabled girl and making her cry.
The teacher just lost it---for above and beyond any reasonable point, however. There's really no excuse for taking it to that level. She'll never teach again.