Snapchat can be a really fun app to use because it’s spontaneous and captures the moment and usually this is a positive thing. If this is a recent issue and it hasn’t been happening for very long, it may just be that this girl is just going overboard with her Snapchat activity and you happen to be on the receiving end. Have you thought that it might not just be you that she’s targeting? It’s possible that she’s just taking lots of snaps of lots of people and doesn’t realise that she’s upsetting anyone. If this is the case, have a quiet word with her.
If, however, you’re convinced that this girl is targeting you specifically and that her motive is malicious rather than fun, then it’s probably time to speak to someone else about it. Explain that you find it upsetting and that you’re not sure how to deal with it. It happens to be Safer Internet Day this month, which could be a good way for your teacher to speak to the entire class about the dos and don’ts of internet use.
No one should take photos of you without your permission, but sometimes it’s hard to put a stop to this. I’m sure your teacher will be able to deal with it during a SPHE lesson if he or she was asked to. If you’re not comfortable discussing it with a teacher, perhaps one of your parents could discuss it with someone at school so that some action can be taken. Don’t forget, you can easily block this girl on Snapchat and if she’s not getting a reaction from you, the chances are she’ll soon get bored and give up.