OK I'll have a go. They are all reasonably sharp and exposed - so good work on that. You have blown out the mesh fence you are shooting through and I can't see much image degradation so that hasn't caused too much of an issue. From a technical camera point of view I think they are fine - where I think you could improve is in composition and in shooting "action".
1) You have clipped the base of the foot and cropped at the knee. In fact the whole frame is cropped very tight. Little context to the image. It might work as an event image for sale to the person in the shot but otherwise doesn't tell me much as a sports image.
2) Better. You have some action - both feet off the ground. I'd crop the red shirted girl on the LHS out and maybe even clone out the hook of the stick near the ball. Ideally you would have been wider to get that opposing tackler in - which would also have stopped you cropping the head off the other player in the background.
3) Fairly static image and the player in blue disengaging from the action doesn't help.
4) As with 3 - I see disengaged subs and managers/spectators on the bench/background and there really isn't any action.
5) Better action - although it is mainly a bum shot and you needed to be composed to the RHS to get the action and not have 1/3 of the LHS of the frame empty whilst missing the tackle coming in. I'd also probably have cleaned up the astro as well - leaves are distracting on the green.
There also seems to be a general lack of goal mouth action. Were there no short-corners, hits inside the 25, goals ?
Here are three on my blog from a Mens match I covered a while back to give you an idea of my viewpoint and the comments above.
http://www.meonshorestudios.co.uk/blog/2012/03/hockey-photography-guildford-hc-vs-cardiff-uwic/
The other thing is why you were outside the fencing - could you not have got inside ?
