Presents the results of an experiment designed to test two hypotheses: (1) a delay of two weeks at room temperature will have no effect on the viability of fertile chicken eggs and (2) refrigeration will have no effect on the viability of fertile chicken eggs. Experimenters were the author and two ninth-grade students. (PEB)

Describes a variation of "the suffocating candle" activity used to develop the process of predicting based on reliable data. Instead of using jars of varying sizes under which the burning time of candles is measured, the same jar is used while the candle is elevated on varying numbers of blocks. (CS)

Provides instructions for constructing a model passive-solar house from a sturdy cardboard box and other readily available materials. By constructing the house and performing related experiments, students begin to understand some of the major principles of solar energy. (JN)

Described are several activities to be used to help students grasp the concept of floating. The activities include the use of a spring scale to measure the weight of the objects in air, in water, and in salt water, and a discussion of why there are differences in these weights. (DS)