first is best except the blue spot at the bottom of the pole. The last one would have been good if taken very wide angle.

it wouldnt have worked.. firstly there was a river behind me (i was actually in a bush trying to get further away) and secondly thers are trees and bushes to the left with dont look good

Last one is my favorite. the shadow//black and white makes it unique.
Not often do you see a good picture with a centered subject.
The symetry is quite nice.

I really like the last one, where the shadow of the tree is its prolongation!

doing gcse photography at the moment, any advice?

The first and the last one are my favorites.

Both have a very individual note and atmosphere.
The play with shadows and illuminated/dark parts looks absolutely fantastic!