The attacks left Kristopher with badly bruised legs, back and ribs. It's so bad that doctors said he needs an operation on his back and feet.
Now his mum, Diane, is going to sue education bosses, saying the bullies could've wrecked her son's career as a dancer.
Kristopher, from Spondon, has been dancing since he was four, and being a ballet dancer is his dream. But bullies at Asterdale Primary School picked on him because of it.
'Ruin it all'