Build all 5 Simple Machines at the same time! Students can construct, examine and explain simple machines to develop a deeper understanding of how they make work easier. A 5 - in - 1 value! Contains enough pieces to build a lever, pulley, inclined plane, wheel and axle, and wedge - all at the same time. Modify machines with 4 included weights (two 5g and two 10 g) and 8 included rubber bands to explore effort, force, load, motion and distance. Labeled pieces assemble easily and separate to store. Set of 63 pieces includes Activity Guide Grades 5+   WARNING: CHOKING HAZARD - Small parts. Not for children under 3 yrs.