Xbox 360 local co-op game for use in science experiment

My son, wife and I are doing a science experiment for his school. He chose to test which batteries last the longest when used in a game controller. Here's the problem. We need a good local co-op game for all three of us to play. We have enjoyed anything from Trials to Castle Crashers, but would probably prefer something toward the hack and slash of Castle Crashers. At the very least we would like to play something we can be all on the same team working toward a goal. Any help is appreciated.

Halo Reach, Gears of War 3, FIFA 14, Battleblock Theater, Geometry Wars 2.

I like the idea of Halo Reach or Gears 3, but how does the co-op work with three people at once?

System link/LAN or all connected to Xbox Live. I like the idea but due to how battery life can vary when you add the vibration variable, it's a bit complicated. I guess you will turn off the option for the sake of the experiment.

I'm pretty sure Halo 3 allowed for up to 3 guests back in its heyday, but I'm not positive.

I would like thank everyone for the suggestions. We wound up choosing Diablo 3 since we can all be on the same screen. I will definitely look at turning off the vibration function per your suggestion to level the playing field as it were.

Marvel Ultimate Alliance 1 and/or 2 would be a better choice, depending on your kid's age

I did an experiment a loooong time ago about the graphic differences between Gamecube, Xbox, and PS2 (and PC was in there as a side thing, since it was unfair obviously) I showed screenshots of the same game across all three with examples of aliasing, fog, specific features like one console being able to handle bots, and a bunch of other BS

It was right before Doom 3 was coming out too and I added in a bunch of fancy words I learned from id Software interviews