PBS
Pbs Teachers: Scientific American: Calls of the Wild: Bats and Echolocation
Explore bats' navigation systems by experimenting with echolocation. Approximate an object's distance by analyzing reflected sound waves, measuring the delay in sound and calculating the ratio to the speed of sound.
PBS
Pbs: Scientific American Frontiers: Teaching Gude: Healthy Choices
Through this activity, high school learners keep track of what they eat everyday and compare their nutrient intake with the minimum requirements for good health.