The “Dropper Popper” bounces about 2 meters high, no matter what height it is released from.
The rubber half-sphere (as seen on left, in above image), can be turned inside out (as seen on right). Stored energy is instantly released when popper turns right-side-out; and, if resting on a flat surface, will launch about 2 meters high. To trigger this, popper must be dropped, flat, onto a hard surface.
Hold and release popper as shown in top image, away from body.
If having difficulty dropping it perfectly flat, spin it like a frisbee while releasing.
Glass has a very high coefficient of restitution. This makes glass marbles very bouncy, if dropped on very hard surfaces. When a marble is dropped onto the head of a hardened steel hammer (as shown on the left in the above photo) the marble bounces almost back up to the height of release. If dropped onto the surface of non-hardened steel (as shown on the right) the marble only bounces about 2/3 of the way back up.