My DS 14 has FB , Twitter,two email accounts one for the aforementioned to deal with junk etc as do I.
From pre teen years when he asked to join Club Penguin we started to talk about online safety. PS keep an eye on those penguins some can spout some filth! Though there is a reporting button...
This subject is hot subject amongst my friends at the moment.
There are those who choose to not look as they believe it is an invasion of privacy but wouldn't know how to anyway as they do not use the different social media platforms.
Those who use various media are a bit more savvy, tend to have more open discussions of the usage of them and the kids tend to be more educated in what is appropriate and what is not.
In the past two weeks alone I have seen naked selfies (girls &boys), posts regarding self harming and huge amounts of horrific bullying (pics involved). This comes to my DS's Twitter feed as they are from his class mates/friends of whom he follows.
I don't "follow" DS as it is not cool to have your mum on your list but he knows that anyone can see his posts and see his followers etc and see what they post etc
In the past week other parents and myself have seen quite frankly shocking pics and posts circulated amongst our kids peer group by other kids who do treat social media as a private diary/blog.
Would you want others to inform you? As to be honest we don't have a choice now, as we have picked up on how bad the situation has got. Someone has to.