Need Help with this video game?

I was helping my nephew with the new Toy Story 3 video game on the D.S. And there was a level where woody had to rescue his freinds from the garbage dump. So i found rex the dino. and found buzz. But when i found buzz i ha to crack rocks... When i'm done though i don't know what to do becuz i can't movie anymore... Its like i have to do something after cracking the rocks...but what???