It's a new school year with the same old problems: the school is going to run out of money! A local engineering competition might just keep them funded for another year. Can Millie and her friends Pearl and Halinka invent a way out of the mess? With some guidance from their eccentric headmistress Miss Bunsen, anything seems possible.

The girls at Miss Bunsen's are excited at the news that Nova Celeste, the famous astronaut, is offering space camp scholarships to three lucky students. All the winning team has to do is invent a flying machine—in just a week! The girls don't have much to work with, but during a sewing class, they stumble across an incredible idea. But will it fly?