ok so she was just studying here, she was not employed by them? I assumed when you said dismissed that she was employed by them...
Anyway, data protection only covers personal data, that is data from which a living individual can be identified. Homework could amount to personal data if it can be used to identify her, so if she has her name on the documents or anything else from which she can be personally identified.
However, just because something is personal data does not mean that no one can’t access it. they can as long as there is a clear policy allowing them to do so. Therefore, that is where school policies would come in. For example, they could say that anything which is stored on school property (i.e. on their servers or hard drives) is not protected and can be accessed if necessary and if required in the specific circumstances.
So a right to privacy does exist but that is not unconditional. If there were specific policies allowing them to do this then they could have done it but she needs to check if this was the case, otherwise there could have been a breach of data protection.
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