stubborn pony tips needed

[spotsmum]

Hi a girl at our yard has a lovely 13.2 cob. He can work lovely as is no trouble out hacking. In the school he plants his feet and refuses to move!I am not a big believer in crops for kids, but never met a more stubborn pony!! He goes at the front out hacking never naps etc, but is a pain in the chool. An ideas?

 

[spotsmum]

Watched her today and now got a good idea. She really boots him on, then as he leaps forward she pulls on reins!!! Few stern words from me, and told to takeher legs off completly, I followed him, told her to tell him walk on, and tapped him with branch off tree. took reins offf her too. In 20 min was responding to voice only, no leg. Typical case of kids and thinking they know it all. She will be back to lunge lessons and no reins etc. I really dont have the time to spend, but feel for the little cob. Girl is not stroppy, but a little knowledge is dangerous!!!!!!