Presents the Astro-Blaster as a method of the laws of conservation of momentum and energy during the creation of a supernova. Several elastic balls are aligned for a drop, followed by multiple collisions which result in the top ball reaching tremendous heights relative to the drop height. (JRH)

Discusses the definition of energy found in many high school and college level physics texts, the conflict of that definition with the second law of thermodynamics, and the relation to the concept of the conservation of energy. Suggests not using a definition of energy and provides some alternative strategies. (JM)

Describes some inexpensive activities and demonstrations that illustrate basic concepts that are often overlooked, as a low-cost means to foster student participation in physics classes. Activities described deal with acceleration and forces, freefall, conservation of energy and momentum, conservation of angular momentum, and resonance. (JRH)