K.R.
Boys at that age really like racing games. Of course you would want to get them games that are age appropriate, and not any rated 'R' games. It will show the rating on the front of the cover.
YOu can ask the clerk at the store that you go to which games are top sellers for boys and girls their ages, and I find that they are extremely helpful. I go to gamestop for my kids games. You can also go to gamestop.com and look up the top sellers.