Singing Testimonies. Of course I've only used these in Jr. Primary since the Sr. Primary kids are much to dignified to respond to such silly things but they are extremely popular.
When I use these I pull them out and explain that my handy helpers have come to primary to help us out. I explain that they have 5 ears to help them listen to how reverent the kids are and how well they are singing. We have lots of fun and I just go out of my way to be silly with them. They go around and touch the kids' fingers and teach song actions and get shy when the kids are too loud. Just make them do whatever you want and the kids love them.