What exam board does she sit Hmmm? Also, do you know if she is doing English Language, English Literature, or both?
For GCSE English Literature (AQA board) she should definitely be studying a 'modern text', and the choices are Lord of the Flies, The Woman in Black, An Inspector Calls, The Crucible, a selection of short stories from an anthology called Sunlight on the Grass, DNA, Martyn Pig Kindertransport or Under Milk Wood.
Then for 'other cultures' the choices are To Kill a Mockingbird, Purple Hibiscus, Of Mice and Men, Follow the Rabbit-Proof Fence and Mister Pip.
After this point it is a little more confusing but she should definitely be doing a selection of poetry and at least one Shakespeare text.
For English Language they do have to submit a controlled assessment on a reading topic, and most schools of course do one of the texts studied for English Lit. If she is definitely doing Lit, it's just unbelieveably lazy they aren't reading the text with them and I would definitely query this. To be honest I think she may struggle to reach her A* target with just a film to rely on!