Parents need to know: This CD covers three Brittney Spears songs (Stronger, Toxic, and Me Aganist the Music), there's a lot of sexual innuedo in Teenage Dream ('Let's go all the way tonight, no regrets, just love"). In Empire State of Mind, there's on line that says "Jigga, I'd be spiked." or something along those lines, since Glee changed the lyrics from a word starting with N. Most kids have heard all of the edgy songs on this CD, I'd say it's fine for them.
My review - I love Glee. I really do. But like the second season, this CD seems weak. You won't find any Queen or Journey covers on this CD. Instead, you'll find Bruno Mars and Cee Lo. Many of the songs, such as Just the Way you Are, just sound like overtuned-messes. This CD is a waste of the Glee cast's talents. There are, however, a few exceptions. Stand-out tracks include a haunting rendition of "I Want to Hold Your Hand" sung by Chris Colfer (Kurt Hummel) and a lively "Valerie" cover sung by Naya Rivera (Santana Lopez). I'd also suggest listening to Darren Criss's acapella Teenage Dream, Rivera and Amber Riley's River Deep Mountain High, and "One of Us", sung by the whole cast.