I would suggest that you get the teachers side of the situation first, so you can decide for yourself what is going on. I always approach teachers with, "she mentioned that something was up with..... could you fill me in?" Because from my own experience teachers can be very defensive. And then address it with, "what do you think we can do together to remedy the situation."
I'll share one of my favorite life lessons:
My oldest was accused of cheating in second grade. The teacher left spelling words on the board and the calendar up. She said, "don't look." Well, she ripped up my daughters spelling test and accused her of cheating. I contacted the teacher and asked her what exactly happened. She said that my daughter looked. From there she said it wasn't a big deal. I said oh yes, it is. If she's cheating in second grade can you imagine what she'll be doing by seventh? Then I asked, did you really leave the words on the board and the calendar up, (the month was a spelling word), and she did, and she expected them to not look up. Well my daughter was a great speller, still is, she didn't need to look. My point being, what the teacher did was beyond stupid. It was like Christmas, put the packages under the tree and they are going to look. She humiliated my daughter because of her own lack of preparedness.
Good luck. I will suggest that you visit with your daughter frequently about her day, and don't let her answer yes or no!