Barometers record air pressure, which is the weight of air pressing down on the Earth’s surface.
- recycled small clear plastic bottle
- 4 craft sticks
- food coloring
- 2 rubber bands
- EHA Barometer Sheet
- Rubber band 4 craft sticks to the outside of the plastic bottle. Make sure the ends of the pencils are even and stick out above the top of the bottle.
- Half fill the bowl and the bottle with water. Add food coloring if desired.
- Cover the mouth of the bottle with your hand then carefully turn it upside down and place it in the bowl.
- Mark the water level in the bottle with a small piece of colored tape or a permanent marker.
- Each morning and afternoon check the water level. Is it the same or is it above or below the mark on the bottle.
- Record the data on the EHA Barometer Sheet
- Compare morning and afternoon readings.
- Compare different days.
- Graph the data.