Flying Machines 1st-8th Build a rubber-band-powered flyer, design symmetrical wings, and test how each design flies. From $4.20 Blendies Pre-K-8th Build a spinning top, then color it so red, yellow, and blue blend into new colors as it spins. From $4.88 Eyelusions 2nd-8th Build a motorized spinner and draw two half-pictures that merge into one image as it spins. From $4.88 Wind-Up Vehicles 2nd-8th Build a car powered by a wind-up spring, then rebuild it to invent a unique vehicle of your own design. From $4.20 Monster Claws 3rd-8th Build a claw mechanism powered by air, using pistons, a tube, and cardboard levers. From $4.88 Art Machines K-5th Build a kinetic sculpture from levers and fulcra, then turn it into a character with its own story. From $4.20 Hypnotizers K-5th Build a wind-up machine that draws colorful spirals and moiré patterns by itself. From $4.88 Crankie Contraptions 1st-8th Build a hand-turned cardboard theater and illustrate a story that scrolls across its screen. From $4.88 Mazes K-8th Use gravity to guide a ball down a path of ramps from start to finish, then connect your maze with a partner's. From $4.88 Drawbots 2nd-8th Build a vibrating machine with marker legs that makes its own abstract art, then rebuild it to draw something new. From $4.88 Scene Machines 2nd-8th Build a hand-cranked automaton, then create the characters and story it brings to life. From $4.20 Monster Mouths K-5th Design a monster with an air-powered mouth that opens and closes, then give it a face and a backstory. From $4.20 Screen Machines 1st-8th Build a cardboard scrolling screen, then write and illustrate a story that plays like a tiny movie. From $4.20 Straw Structures Pre-K-8th Join jumbo paper straws into shapes and 3D structures, from towers as tall as learners to team builds that reach the ceiling. From $4.88 Linkages K-8th Build linkage mechanisms from cardboard levers and pivots, then camouflage them to create a scene that tells a story. From $4.88 Strawbots 2nd-8th Engineer a machine that moves by vibration by connecting straws to motorized parts, then turn it into a creature with a personality of its own. From $4.88 Electric Vehicles 3rd-8th Wire a motor and gear into a working electric car, then redesign it to be smaller, faster, or three-wheeled. From $4.88