A simple teaching model, designed to show rapidly which are the principal factors in population growth and how they are related, is presented. The apparatus described allows students to play several different active roles. (MP)

Presents methods for analyzing soil and water samples in this classroom. Includes a classroom diagram, a listing of suggested materials, and the procedures for a classroom simulated pond. Relates classroom activities to work at a natural pond. (MA)

Describes an activity which simulates a trip to the moon. Explains the preparations, procedures, and tests involved in this culminating activity of an astronomy unit for the third grade student. Examples of student's assignments during the exercise are included. (ML)

The development of a spaceflight simulation program as part of a research and development course is described. Topics such as space exploration, design, propulsion, aerodynamics of space craft, robotics, communication, construction, medicine, lasers, hydroponics, geology, chemistry, and space physiology are emphasized. (KR)