I got a mail via my website from a high school student.
The school appears
to take a continent education from junior-high from senior-high.
Every year, students make huge balloons with very light paper.
They designed space-shuttle, ships, and characters from Japanese
Miyazaki's Mononoke-Hime, Totoro, ... )
This year is the 15th anniversary of the balloon projects.
Also 6 years ago, they have used the "Unfold"
Amapi to make balloons.