My 9 y/o daughter has hair almost exactly like your daughter's. She hates it, too. She doesn't get teased at all, though. She gets compliments on her hair constantly, but I think she does not like the attention her "big poofy hair" brings her. I'm hoping to someday get her to wear her hair down again, but it's been years since she has. I am here today to look for help with products, too.
I wish you luck and I wish I had some advice. For now, I'm in the same boat (minus the teasing - and I'm disgusted that it is happening to your child).