absolutely let the coach know. and teach her how to Moutza! and when older, the middle digit.
and based on your previous posts, you probably won't agree with me.
but, it works every time. cause after the kid gives the Moutza or middle digit, the bully comes running to us to snitch on that kid that gave them the hand gesture, whereby snitching on themselves. as you stated, this usually goes on "below the radar". this is so true and we coaches can't catch this stuff all the time.
you see, we then call over the kid that gave the hand gesture. we inquire as to why he/she performed that hand act. and the kid states that "so and so" called her fat and ugly.
of course, initially, the bully denies it. but then we question the bully as to why the other kid would just inexplicably give them the Moutza or finger. they finally fess up. and we let the bully know that each and every time the one that is being bullied by them will give them the Moutza or finger. the 2 then become best friends and allies cause receiving the Moutza or finger is much more humiliating than being bullied AND it empowers the one being bullied.
this is a plan that we approve with the parents so that they are aware of HOW we will solve the problem. and they must let their kids know that this method is for in the gym only. it's more intimate, understand? and in this way, the one being bullied does not have to be the one that snitches also. that's double pressure. we can ALWAYS depend on the bully snitching. try it and you'll see. and what about the bully's parents you ask? you really think the bully goes home and tells their parents what happened?? no way. lol.
and some of you will disagree. and yes, happychaos's daughter is only 9. but she's being pushed around by middle schooler's. unfair fight. the hand gestures level the playing field and out the bully. over time, most gyms will just kick out the bullies. i don't think this is productive as it does nothing to solve that person's problem that they are having with themselves. bully's bully for a reason.
and i don't want people to think this is a regular occurrence for our gym. it's not. and used in only special circumstances. but it works. kids will be mean.
one of my strongest (empowering) memories was watching my Mother (Italian) give some guy the finger in the grocery store back in New York when i was a child. the look on his face is is etched in my mind for all time.