Discover art and science in a myriad of spherical reflections.

Silver Christmas tree balls packed together in a single layer in a box create an array of spherical reflectors. Each sphere reflects a unique image of the world. Study the properties of spherical mirrors while you create a colorful mosaic of reflections.

Silver Christmas tree balls [...]

A clueless way to determine the size of an object.

You can trick your brain into thinking that two similar objects of different sizes are really the same size. This is done by removing clues to the actual size and distance of the objects. You can then compare what you see when you limit your [...]

Catch a retinal net

You can use a dim point of light to cast a shadow of the blood supply of your retina onto the retina itself. This will allow you to see the blood supply of your retina, and even your blind spot.

A [...]

One reason not all buildings are equal in an earthquake.

This device graphically demonstrates that objects of different sizes and stiffnesses tend to vibrate at different frequencies.

A sheet of cardboard measuring 1 foot (30 cm) long and several inches wide.
A large sheet of construction paper (about 14 x 20 inches [...]

If you want to stay hidden, you’d better stay still.

Some animals blend in with their surroundings so well that they’re nearly impossible to see. Only when these animals move can you detect their presence and shape. With this Snack, you can compare what you see when a camouflaged figure remains still to what you [...]