Our Cool After School program on January 19 featured optical illusions from the fabulous book, Eye-Popping Optical Illusions, by Michael DiSpezio.
We made phenakistoscopes, and experimented with creating our own animations.
A phenokistoscope is an early animation device invented in 1832 by the Belgian physicist, Joseph Plateau.
It consists of a spinning disk and a mirror. The disk is slotted and has images on the side facing the mirror. 
Looking through the slots at images reflected in the mirror as the disk spins gives the effect of moving pictures. For some cool examples, check out the Teach Animation site!
We also made a monster with eyes that seemed to follow your every move. Note the matching fangs on this pair!
Younger kids had trouble focusing through the slots on the images reflected in the mirror, and could not see the animation.
But everyone could see the illusion of the monster’s moving eyes (which were on a separate piece of paper attached in such a way that the eyes on the loop of paper were viewed through the eye openings on the face of the monster).
