I just finished a pretty decent book called "Sticks and Stones". Got it at the library, don't remember the author's name. I didn't agree with all the advice, but some of it was good, and even better, it was practical. There were examples of what your child could say in response to such and such teasing, bullying, etc. There were scripts and role plays to read out loud together. Maybe that will help you! It's helped me respond to my 9 yo dsd when she talks about stuff kids say to her at school.