An Electric Fish emits pulses of electricity into the water, with which it locates food, other fish, and potential mates. It is easy to listen in on these electrical signals with simple inexpensive equipment, such as a piezoelectric earphone, or a small amplifier.
http://sci-toys.com/scitoys/scitoys/biology/electric_fish/electric_fish.html
Students will use a CO2 Gas Sensor to measure the amount of CO2 in their breath as they exhale, both before and after exercise.
http://www.pasco.com/experiments/biology/december_2002/home.html
When an egg is boiled, some of the air in its air pockets escapes and is replaced by water. Measure the difference in density of an egg before and after boiling it.
http://www.sciencebuddies.com/mentoring/project_ideas/Chem_p007.shtml
Students will use a Skin/Surface Temperature Probe to measure the change in skin temperature before and after applying both a cold pack and heat pack to a student's arm.
http://www.pasco.com/experiments/biology/february_2003/home.html
Butterflies don't look like caterpillars. What's the connection?
http://www.hhmi.org/coolscience/butterfly/index.html
Investigate a flower’s power of marketing by making an imitation flower that successfully signals a bee (or other pollinator of your choice) to visit.
http://www.tryscience.org/experiments/experiments_botany_athome.html
Discover how sensitive a shark's sense of smell is
http://www.tryscience.org/experiments/experiments_sharksense_athome.html
Measure turbidity, or the amount of sediment suspended in water, and learn how turbidity affects aquatic life
http://www.tryscience.org/experiments/experiments_turbidity_athome.html
Winter snacks for our feathered friends and acquaintances.
http://pbskids.org/zoom/activities/sci/birdfeeder.html
This experiment was performed to determine whether or not one person's suggestion has as effect on another person's subconscious reactions
http://scssi.scetv.org/mims/schools/blhs/science/y98/ellen1.htm