School violated Student's privacy

So, there is this issue with a 19 year old girl who is suing her former high school because they went through her phone and found semi-nude photos. They are claiming it is an invasion of privacy. I feel they should not have gone through her phone. They have all the right to take her phone but not to go through her phone. What is your opinion on the subject? How would you feel if someone went through your phone? Do you think the school is wrong for doing this or is she wrong?