Tricky trying to teach people (kids or otherwise) about photography, when all they have are compact cameras. Well, some cameras would be fine, but as they will likely each have different cameras, it would be hit and miss.
My first inclination would be that I want to teach them about the basics; aperture, shutter speed and ISO. But some of those cameras probably don't even show you those settings, let alone allow any real control over them. So teaching the kids about them, might not be all that helpful, and it might seem quite boring to them.
So, maybe just touch on those things, explain what they mean, and so the kids can know what they are when/if they do see those numbers on their cameras.
Basic operation of the camera. Also, how to use the auto focus. Maybe touch on the different 'modes' and what they do.
Then I'd probably concentrate on teaching them to think about what they are doing when they take photos. Teach them to choose a goal and maybe even pre-visualize the photo that they want to take, and then try to accomplish it.
A very easy thing to teach, is the rule of thirds. If that is the only thing that they learn, it will still probably improve their photos dramatically, if only because it causes them to think before pressing the button. A trick that I've heard about, is to take little pieces of paper (cut up some Post-it pads) and put a little square right in the middle of the LCD screen. Then tell the students that they have to take photos where the subject isn't hidden by the paper.
And of course, once they have the concept of thinking before taking the photo, give them assignments/homework.
And if you can work it, they would probably get a lot out of reviewing their images while you offer helpful C&C.