The Jane's Evanovich books are funny and light. One for the Money is the first and now is up to 18. They can pretty much be read out of order but after a while are a little predictable.
Lise- i have heard 50 shades of Grey is very steamy. Some places consider some in the series almost pornographic. I have not read it personally.
Any one read I am number four and that series.
Shannon - I've read I Am Number Four and The Power of Six (Lorien Legacies) with my nephew, they aren't bad, but we liked the Maze Runner series by James Dashner better (it's a trilogy). Are you specifically looking for books that your boys would enjoy as well? The Ranger's Apprentice books by John Flanagan are good too...I think they're up to 11 or 12 now...I read the first 5 only. And of course Rick Riordan. Let me know if you need more suggestions - I've read a lot of YA/teen books with my nieces and nephew and my policy is to never "gift" a book or series without reading at least the first book myself (sometimes I'm shocked at what is considered YA)
As for Shades of Grey, I did read the first one - at the request of my aunt. IMHO, it is not nearly as graphic as books like the Black Dagger Brotherhood (which also touches on BDSM with certain characters), but I'm not likley to read the rest of the trilogy. I personally think its not very well written at all - regardless of the story line. The phrase "Inner goddess" must appear at least 100 times. ugh. For me, it was like a bad romance novel. Of course, they are on every best seller list imaginable, so if you're just curious to see what the fuss is about, it is a quick read...but I wouldn't advise reading it in public if you blush easily!
BTW - I love the Black Dagger series - again, not exactly award winning prose, but very entertaining!