What is a watt? This tongue-twisting, mind-bending question and others are answered through this activity on the different lighting options available. With the support of a PowerPoint, teach your physical science class about units of measurement, energy use per capita, and four different types of light bulbs. Learners look at each bulb type and rank them, both before and after learning about their heat emission, energy required, brightness, color, costs, and health impacts.