Things You'll Need:
- Empty paper towel roll
- Tape
- Straw
- Glass jar with 2- or 3-inch opening
- 12-inch balloon
- Sturdy rubber band
- Scissor
- String
-
Step 1
Cut open the balloon and tightly spread the balloon around the top of the jar. Be careful not to poke a hole in the balloon, as the jar has to be airtight.
-
Step 2
Secure the balloon to the jar. First use the strong rubber and to initially attach the balloon to the jar. Then, reinforce the balloon by tying string around mouth of the jar where the balloon overlaps. Tie the string tightly.
-
Step 3
Create the measuring needle by cutting the straw to a length of about 6-inches.
-
Step 4
Cut approximately 1/4 inch off each end of the straw at a 45-degree angle. The angles on each end of the barometer needle must be opposite of each other. In other words, one end of the straws 45-degree angle faces the ceiling while the other 45-degree angle faces the floor.
-
Step 5
Tape the straw to the top of the balloon. Using the side with the 45-degree angle opening facing the ceiling, tape the flat side of the straw to the balloon. The tip of the straw must be in the exact middle of the barometer’s surface. Accurate placement will ensure accurate barometer readings. The opposite end of the straw will have the 45-degree angle opening facing the floor. It will serve as the measurement reader.
-
Step 6
Create the barometer measurement chart by making marks on the paper towel roll. Take the barometer and the roll of paper towel outside. Make a note of the level at which the straw is pointing to the paper towel roll. Mark the level and write or draw a picture of the current weather conditions. For example if it’s sunny, draw a sun; if it's rainy, draw raindrops. Repeat this step over the next few days until you’ve successfully mapped all available weather conditions.
-
Step 7
Chart the changing weather conditions. Now that you’ve completed your barometer, just sit back watch and chart the current and changing weather conditions.
