Kes (1969) directed by Ken Loach
http://www.imdb.com/title/tt0064541/
I last saw this years ago on TV when I was a child. I remember it was striking that I recently bought the DVD to look again. It's about a scrawny lad growing up in Barnsley where everyone is trying to put him down. He finds solace in training a young kestrel that he has stolen from a nest. There's some great scenes of him training the bird to a lure. David Bradley who plays the boy, Billy, gives a tremendous performance that outshines everyone else - including Colin Welland who plays the sympathetic teacher and Brian Glover, the sadistic games master. (Several scenes of boys in showers - weren't they all skinny then!). The dialogue is very 'Bratford' so you'll need a keen ear to hear it all and the style is very TV orientated (not suprising since Ken Loach cut his teeth on Z-Cars). It's very dated but, IMHO, still a classic piece that is well worth watching.