The great thing about children taking photographs is that they see the world through such young eyes and the subjects they photograph are usually dismissed by adults. I remember seeing a show at Art Institute of Chicago where the exhibit consisted entirely of work by children. there were some really beautiful and moving images.
I had once investigated the idea of finding a corporate sponsor to help pay for a project that would involve finding children in every country to send one or two disposable cameras to and then have the cameras shipped back and then provide a gallery on the internet and maybe an exhibition somewhere. A sponsor such as UPS or Fed Ex would be ideal because they could provide the logistics of getting the cameras to and from virtually any country in the world. Contacts could be made through embassies or volunteer and relief organizations.
i beleive kodak has a similar type of thing going, but the last time I looked, it involved mostly European contries or probably countries where Kodak products are sold.
I think it would be very interseting to see the similarites and differences of how children would use there 24 or 48 exposures.