With any luck you'll discover that your teenage kids are simply having fun chatting with other teenagers online and making a few new friends.
If you're worried about them at all, at least if you're online too, you'll get a better picture of who they are mixing with and what kind of things they're discussing.
You don't even have to be 'friends' with them on Facebook or 'followers' on Twitter.
If you are signed in to your own account on Facebook or Twitter you can search by name and get a basic idea of what they're up to.
If you're not comfortable with that - be honest and tell them you've joined up and would like to be friends! You may be surprised to discover that Facebook and Twitter are great ways to communicate with your teenagers online.
Teenagers are notoriously bad at talking with their parents so why not join them in a place where they are more comfortable and more likely to exchange messages and information? You may also be surprised to find that Facebook and Twitter are not just for young people.
There's plenty of fun to be had by the over 30s, 40s and beyond! Why not sign up for Facebook and/or Twitter if you haven't already, have some fun and check that your teenage kids are keeping safe online at the same time.