What film is this(description of film)?

[iamdeadbiteme]

A girl lives with her dad and he has to go to war so he takes her to either a care home or a boarding school (I think it's a boarding school) and the they have to wear a green uniform. The girl tells loads of stories about this Indian couple(I think) and the owner of the boarding school doesn't like her, she takes her necklace off her as a punishment and when the girl gets the locket back the women rings the police and the girl has to cross a plank off wood to the building opposite and finds her dad in there but he has memory loss from the war, does anyone know what the film is called??