Social Media and Online Identities

I admit that I am somewhat behind the power curve when it comes to social media.  I rely too much on my wife and kids to keep me informed.  I am a little apprehensive as my former training has taught me a lot about the dangers of social media, however, I do have a Facebook, Twitter and LinkedIn accounts.  That is about the extent of it, I have them, but rarely use them, not sure that they are completely set up yet, let alone correctly.  I am a substitute teacher, google along with classroom gives me all that I need at this point.