Puzzle difficulty when chosen correctly

This hands-on kit includes 26 model-building exercises that progress from basic to complex

Daniel Barenboim

Malala spoke out in public about this

for ages 18+ mos

SpringBots 3-in-1 Spring-Powered Machines slow food Puzzle difficulty when chosen correctlyHow cool is it that the mainspring stores energy, then converts it to motion? Discover the physics of potential and kinetic energy and the inner workings of gears and springs as you assemble the different mechanical devices. No batteries or electricity required, these models are self powered and super cool. Follow the detailed instructions and you'll wind up winding up a robot, racecar, and timer. From Thames & Kosmos, for ages 6 12 yrs. Watch the