I take it your doing AS photography then seeing as i did that stuff last year.
what you have to understand is AS photography doesnt matter so much on what you wright in the book. Just how you link things, when your book gets marked i can safely say theres a 99% chance the marker wont even read what you've put.
The sure-fire way of getting a good grade in Photography A level is repeating the same things in all of your sketchbooks. Once you work out the fraework of how to set out your sketchbook you can get a whole unit done in a matter of weeks.
Basically the best way to do it is..
Initial images that flare your idea for the project. (dont have to all be from the same photographer/artist but naming them does keep the teacher happy)
Shoot 1 contact sheet
Shoot 1 best images
Shoot 1 Image edits (use screen grabs to show how you edited them i.e. contrast levels etc)
Artist/Photographer research that lnks with your idea.
Try re-creating some of their work, or photograph similar things.
Shoot 2 contact sheet (use what you learned from the artist research in this shoot)
Shoot 2 best images
Shoot 2 edits (screen grabs like last time)
Artist/Photographer research, this time try to link it to something new. I was doing urban landscapes and researching Mrk Goldsteins work, then i found he does Macro stuff of rust and wood etc. so i moved on to macro work.
Shoot 3 contact sheet
Shoot 3 best images
Shoot 3 edits
Final Piece composition ideas
Final Piece decided composition
then just mount your final images and your done =D
If you keep this in mind when your doing a sketchbook then you'll always know what your doing next. Infact maybe when you get your sketchbook write on the pages in pencil what will be going on that page. That way you dont waste time pondering what to do next.
Hope that helps..