My inspiration came from a project two coworkers did with all of the students in our school. They worked with every student in the school to create a balloon lantern for an evening whole school parade. You can see some images of our school parade at Amy Donohue Photography's blog post on a Full Moon Lantern Parade.
As I helped with my students in the art room I knew this was definitely something we would have to try at home at some point. I had envisioned creating a whole set of planets for Big Brother's Outer Space Birthday party, but later realized it would be a great project for Earth Day.