I was playing the silly question game in class with my students last year (where we take turns asking each other silly questions like, "Do you like butterfly ice cream?"), and without thinking I was answering some of their questions with "Uh-huh", and "Unh-unh." The kids latched on to it and started mimicking me, but it's not as easy for non-native speakers to say as you might think. It's all in the nose, so you can't show someone how to pronounce it, and the stress pattern is not easy to grasp at first.
Sooooo, we made a simple song that would bounce around in the kids' heads and we have had a great time singing it in class, everybody nodding their heads up and down and side to side. It's called Uh-huh! and it's on the Super Simple Songs 2 CD.
Last week, Jeremy-sensei disappeared into one of our classrooms for an hour or so with his laptop, 2 puppets, and a copy of Super Simple Songs 2, and emerged with this classic video for Uh-huh! I hope you enjoy it as much as we have!