Describes the objectives and content of a freshman physics laboratory course designed to eliminate the cook-book type of experiments. Instead, students are encouraged to devise their own experimental designs, execute the experiments, and interpret the results in their own way. The authors report that student reaction to the course is generally…

The diffraction of a full thermal atomic potassium beam by a single slit was observed. Four experimental diffraction patterns were compared with that predicted by de Brogtie's hypothesis and simple scalar Fresnel diffraction theory. Possible reasons for the differences were discussed. (LC)

The continuing erosion of financial support for undergraduate laboratories makes cost an increasingly important factor in the choice of undergraduate animal experiments. Projects employing insect predation by rodents, which require minimal equipment and pose a number of interesting questions about animal behavior, are described. (RM)

The author proposes a design for science instruction in the middle school years, ages 9-13. (SJL)

Describes the use of ethyl or methyl ethanoate mixed with trichloromethane to illustrate intermolecular forces and deviations from Raoult's Law. (MLH)