I'm certainely not a jumping position expert, but I thought I would take a crack at critiqueing :3.
It's hard to tell, but I think you need to move your stirrup iron up closer to your toe, it'll help you put your heels down more. You're jumping ahead of the motion ( I do that too, reason why I fell off the other day x|) and you have a roach or hunched back. In the fifth picture though, you got left behind because your horse had a big jump over that log. Your knee pinched, which caused your leg to slide back.
That's all I got :).
Oh and what eventnwithwinston said about her knees, it shouldn't be a big problem at your level, but gymnastics may help her snap up her knees a little more :P.
Last edited by drafteventer; 08-29-2009 at 02:57 PM.
Reason: typos and such