你怕什么？

Dear Principal and Class Teacher [insert names],

For my daughter NAME' personal safety, you must separate her from CHILD NAME before CHILD NAME inflicts serious bodily injuries on NAME.  Today, CHILD NAME intentionally stepped on NAME's hair while NAME was jumping off the play set and caused injury to NAME's scalp.  I need to rely on no other eye witness for the incident but myself because the incident took place right in front of my eyes.  

We have reported to CLASS TEACHER that CHILD NAME has inflicted injuries to NAME's wrists numerous times.  I can no longer be satisfied with any measures short of physically placing them in separate classes.  I respectfully urge your honoring my request.  

Sincerely,

YOUR NAME