My first reaction: Guess she's not a fan of the "tough love" scenario....

What the teacher did is completely inappropriate and does nothing for anyone's self-esteem. There are other ways that might actually motivate a child. However, I also wonder just how many assignments this child has turned in where it's obvious she doesn't care about what she's doing and it shows. And let's bring in mom on this one too. What's she doing to make sure the child can study and/or get the help she needs if she's not understanding the material being taught. This has been going on all year, and we're going to focus on the "loser" comment rather than finding out why she's struggling? The system is screwed up.