Explains what optical illusions are and offers many examples to try.

A webpage on optical illusions, containing a grid of black squares, an elephant with four or five legs, and a picture with three faces in it.

This resource contains some optical illusions that will boggle your mind as you try to figure them out.

A collection of information on the science of light and optics. Features a wide variety of resources: key events in history, reference materials, multimedia links, optical illusion activities, glossary of optics terms, and information on...

In this lesson make a spinning top to explore the concepts of shape, color, spinning, and optical illusions.

A great resource to discover fun new activities to use in your classroom. Activities are age-appropriate, and span several science topics.

An optical illusion created using Leonardo's well-known portrait of the Mona Lisa serves as source material for an exercise in perception.

Two examples of optical illusions that demonstrate aspects of how we perceive color.

This site from Hanover College gives a tutorial on issues of visual representation, such as depth, perspective, texture, shadow, illusion. Begins at an introductory level. Numerous pictures.

This optical illusion image is known as a Fraser spiral illusion, or false spiral. The black arcs appear to form a spiral when in fact they are a series of concentric circles.

This optical illusion, known as the Orbison illusion, gives the effect that the rectangle and inner square are distorted. This effect is caused by the horizontal V shaped lines.

This face and vase picture is a very common optical illusion. Do you a white vase or two identical black faces looking at each other?

This black and white image is a very famous example of an optical illusion. Designed and drawn by C. Allan Gilbert, the name of the image is 'All is Vanity'. It represents both life and death where the meaning of existence is intertwined.

These are two simple missing shape optical illusions shown in black and white. The existence of a white triangle can easily be imagined in the top image while your brain can also easily create the existence of a white sphere in the lower...

This excellent optical illusion is confusing because when you look at it, it appears that the nine wheels are moving, when in fact they are not.

This famous optical illusion makes the parallel horizontal lines appear to be bent when in fact they are straight. It was originally noticed amongst the tiles of a cafe wall and can now be seen in architecture such as on a large building...

Does this optical illusion show a man playing a saxophone or a woman's face? You be the judge.

This is a vertical and horizontal line length optical illusion. The vertical line that is part of the image on the left looks longer than the horizontal line but when it is checked with a ruler on the right image it is proved that they...

Four postcard-sized optical illusions that can be used to demonstrate how patterns and color influence perception.

An optical illusion that demonstrates the effect of eye movement on perception.

The following picture is an example of an afterimage, a type of optical illusion that continues to appear in one's vision even after you finish looking at the original image.

The Bezold effect is named after Wilhelm von Bezold, a German professor of meteorology. It is an optical illusion that makes colors look different depending on their relation to adjacent colors. It works with small sections of color...

Hunkin's Experiments is a group of simple cartoon illustrations of scientific principles. Some would work well in the classroom, but others have little value beyond entertaining students. All of the projects are easy to do and use...