Create your own action-packed marble run obstacle course with this interactive GraviTrax Speed Set construction toy for kidsThe GraviTrax Speed Set includes height tiles, turns, tunnels, tracks, and 4 different accessories for endless building activities to do on your own or in a groupThis 185-piece STEM toy offers a screen-free activity that fosters problem solving, creativity and experimentation for kids ages 8 and upDesign, build and race the marbles through your own obstacle course tracks and use gravity, magnetism, and kinetics to propel them to the finishUse the included instructions for 10 different track layouts so you can start building and playing within minutesWith over 6 million sold worldwide, GraviTrax makes an awesome birthday present or holiday gift for budding engineers or kids who love to build