What do your kids like to do? Any chance you could integrate a computer with it? My daughter loves to cook and dance and I haven’t found a way to integrate that with computers but she’s happy so I haven’t pressed it.
RoboCup Junior OnStage is a good example of integrating dance with computers. You can program sensors to detect triggers from humans and respond by moving props into place. There's a lot of freedom to choose what type of sensors, computers, and actuators to use. Search for videos of RoboCup OnStage to see some examples.