Little Director is an award-winning service that creates animated movies from children's drawings. They claim that "some of their best works have come from group and class projects" and provide a detailed lesson plan(.doc)
for creating and illustrating the story. Once complete, the movie is easy to share. It's hosted on the Little Director site or you can also order a DVD, which would be great for a fundraiser or just a lovely keepsake. There is a $400 minimun per class, but this includes up to 20 drawings and an audio track (voice and/or music). When I contacted Royi Akavia, the founder and chief animator, to get more details, he replied that for $20/student, each child could receive their own DVD. The Little Director website has a wonderful gallery of school projects. It's really quite amazing what they can do with a simple illustration!