Describes a demonstration for college-level cognitive psychology classes of Miller's "Magical Number Seven" concept of the limitation of sensory capacity for processing information. Students report on the number of pennies they observed in a box after viewing the coins for two seconds. Demonstration results consistently support Miller's…

Describes a perceptual illusion, the Janus mask, for use in introductory psychology demonstrations. Suggests using a motor or videotaped image to rotate the mask, giving the impression that the mask is following a moving observer or oscillating. Recommends the illusion to show that perception is usefully conceptualized as hypothesis testing. (DK)

A laboratory exercise is described in which students view the environment through a transparent frontal parallel plane. The relationship of projected size to distance can be studied, and other cues to distance based on this geometric relationship can be appreciated. (Author/AV)

Maintains that having students estimate the size and width of a class waste paper can (placed on a desk) is a simple and effective way of illustrating perceptual distortion. Tests show that people will consistently overestimate the height of the can, allowing for a useful discussion on sensory distortion. (MJP)

Outlines a simple classroom demonstration that illustrates Piagetian conservation. Piagetian conservation refers to the illusion of an increase in mass by changing an object's form. This demonstration, done by forming an ellipse with an extension cord, shows that college students are as susceptible to this effect as are young children. (MJP)