Snapchat seems to be a favorite among Middle and High School age kids. When asked to be there friend on it, I tell them a couple of rules. 1) If you send me something and I feel it is inappropriate or you are going to harm yourself, I will tell and show the Principal what I received. 2) Remember, if you wouldn't let your parents or grandma see it, then don't send it to me.
Sad to say, I did have one sent to me which contained underage drinking by a student. It broke my heart to see what I saw and then go report it. However, I knew the responsible and appropriate action I needed to take to keep the student and myself safe. The Principal knew it wasn't easy by did thank me for reporting it. My students safety comes first and foremost. Even if it means slightly bruising our relationship.