Discusses enzymes, catalysts, and factors that affect the rate of a chemical reaction. Presents activities based on enzyme action on hydrogen peroxide and lactose intolerance. (Author/JRH)

Describes an activity to give students experience with the variables and forces impacting a moving body on an inclined plane by observing a ball as it rolls down an inclined PVC pipe of fixed length. Includes a student worksheet. (MKR)

Reviews research related to laboratory work and makes recommendations for the classroom on how to make labs more meaningful. Argues that pre- and post-laboratory discussions containing theory behind the lab and purposes of the lab are essential for new understanding. (DDR)

Discusses a number of important laboratory-related terms worthy of consideration and suggests a classification scheme that may be used to rate individual activities while implying a direction to enhance such exercises. Highlights implications of classifying laboratory activities and clarifying laboratory vocabulary. Contains 11 references. (JRH)

Describes two science activities concerning water density and shares an idea for combining these activities into a third, completely new activity. Demonstrates the joy of rekindling the spirit of scientific thinking in a typical classroom. (PVD)