Editor’s Note: Bob Knetzger has been making fun stuff all his life — first as a kid with his trusty Vac•U•Form and Thingmaker toys, then as a professional toy designer at Mattel, and for the last 35 years as an independent toy inventor. He’s been sharing playful projects with Make: in the Toy Inventor’s Notebook for years and now those projects have been gathered from the pages of the magazine into one delightful book, Make: Fun! The book is available now!
The “Diving Spudmarine” is just one of the many fun projects packed into this book. It’s an easy DIY version of the classic cereal premium toy, the baking powder-powered diving submarine. Instead of plastic, this one is made out of potato.