Briefly outlines the theoretical basis of the phenomenon of photoconductivity and describes a simple experiment which demonstrates the photoconductive properties of cadmium sulfide. (JR)

Describes a technique for the supercooling of water, for use in the science classroom, involving adding common salt to a mixture of ice and water. Several investigations are included for use during (and after) the process of supercooling. (DS)

Describes the commercial applications of hydroponics, and then outlines ways in which this soilless plant culture method can be used in the science classroom and laboratory. Gives directions for making a suitable growth solution, and suggests appropriate student experiments involving hydroponics. (JR)

The use of 10cc. syringes in high school chemistry experiments can reduce the expense of equipment and lead to imaginative experimental designs. Describes the equipment and experimental procedures for four experiments utilizing syringes. (JR)

Describes some of the causes and consequences of particulate air pollution. Outlines the experimental procedures for measuring the amount of particulate materials that settles from the air and for observing the nature of particulate air pollution. (JR)

Describes two experiments using carbon dioxide cartridges to demonstrate Newton's third law of motion. (JR)

Describes a number of activities designed to assist student understanding of the phenomenon of light bending when it passes from one meduim to another. (JR)

Light-emitting diodes (LEDs) are described and three classroom experiments are given, one to prove the, low power requirements and efficiency of LEDs, an LED on-off detector circuit, and the third an LED photoelectric smoke detector. (BB)

Describes student activities with mercuric oxide and mercury that help them to form models of the solar system and its creation. (JR)

This experiment, mixing solutions of potassium iodide and lead nitrate to give a bright yellow lead iodide precipitate, often leads students into other topics such as making paint from the precipitate. (BB)

Describes a lab investigation designed to introduce students to soil compaction and help them to learn to design and adapt procedures that scientists use when they plan and conduct controlled investigations. Provided are objectives, a list of materials, procedures, and a sample student handout. (CW)