need suggestions for XBox 360 game for 'tweens'

I grabbed 2 Angel Tree tickets this year: boys, a 10 y.o. and a 12 y.o. I got a handle on what clothes to buy them. However, each also wants an XBox 360 game. I see an @$$load of <$20 options on eBay.

What are some good games for pre-teen boys? Two criteria:
1) Cannot be rated higher than E-10 (e.g. no 'T' or 'M' ratings)
2) Can be fully-played on a basic XBox 360 system. I need to assume that they don't have Kinect, 2nd controller, online access, hard drive, etc.