This website describes all sorts of dice games that can be played by young children. On Monday, we looked at Shut the Door, one of my favorites for young children, but there are so many more great ones.
Some of the games on this site are clearly for older children but there are some that would be perfect for preschool-aged kids. I like “Crazy Faces” that uses the dice to give the children direction about what to put on their paper faces. It takes a little bit of preparation, but your kids will love it.