Builds 5 models a dragster powered by an elastic spring a crash test car a catapult a gravity operated fan and a balloon-powered flying plane</br>Multidimensional construction system Build structures and machines with 114 parts</br>36 page activity book is included with the fun easy to assemble models - more plans can be downloaded from Engino's website</br>Excellent addition to a home-school curriculum</br>Another fun educational product from Elenco the company that brings you Snap Circuits</br></br>Product Description</br></br>Engine Mechanical Science Screws Kit the fun and easy way to learn about physics! Budding engineers will learn how worm gears are used how screws can convert circular to linear motion and more while they have fun building 5 working models! 5 models in all: screw press folding lifting platform 2 cranes and a vice. Included is the 36-page activity book with detailed explanation of the different technological principles applied. 150 piece in all. For kids age 8 and up. Warning: Choking hazard?? for children 8 and up. Order today! Engine Mechanical Science Screws Kit; From the Manufacturer; Engine Mechanical Science: Screws. This Engine set introduces young engineers and physicists to how worm gears are used to gr