How to Make a Kids Barometer

A barometer measures the pressure in the air. This measurement is used to tell whether a sunny day is coming, or a day that may require a raincoat. A homemade barometer will help children understand air pressure and how it affects the weather. Learning this concept can be done strictly with a textbook, but learning is always better hands on. The project uses items you can find at home, so you won't need to spend any money to make it.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• Table Glass jar Stick of gum Straw Tape Ruler Paper Pencil Water Marker

1. Begin building your barometer on a table; you need a flat surface for the project to work. Set a glass jar on the table.

2. Stick your ruler in the glass jar and turn it towards you. Make sure you can see that the 1-inch mark is towards the bottom, with the higher numbers reaching towards the top.

3. Tape the ruler to the glass jar. Make sure the tape is above water level.

4. Put your straw in the glass jar directly next to the ruler. Hold the bottom up to the 1/2-inch mark and then tape it in place. You may need to tape it to the ruler instead of the jar itself.

5. Pour water in to your glass jar until it is half full.

6. Chew up a piece of gum and set it to the side of your cheek. Start sucking water up through the straw and when it gets half way, plug the top end of your straw with your chewed piece of gum.

7. Get out a permanent marker and mark the ruler where the water level is in the straw.

8. Each day record whether the water level in the straw is rising or decreasing.

9. Interpret the data. If the water level inside the straw rises, then the air pressure is increasing. This means weather clear of clouds, rain, snow or storms of any kind. If the water level inside the straw decreases, it means that the air pressure is decreasing, indicating rain, snow or storms.

Tips & Warnings

• Perform this experiment in your home away from any doors or windows. You need a place that has a climate that doesn't change much for the experiment to work properly.