Weather Unit: Experiments about Air

Last week we had a lot of fun with our Weather Unit.  The kids always love when we do science experiments and this part of our unit had a ton of demonstrations.

Air has weight:

This first activity is pretty self explanatory. We made sure that two balloons balanced. Then we blew up one balloon. It was clear immediately that the blown-up balloon was heavier.

Clear or Cloudy Day:

The next activity was supposed to show whether the air heated up more quickly on a clear day or a cloudy day.  Then we were supposed to check to see which lost heat more quickly (we forgot to go back outside late in the day, though).

Warm Air Rises:

This was by far our favorite experiment! It worked so well. First we spent quite a bit of time talking about the movement of air… how warm air rises and cool air sinks. We talked about the term “convection.” We also talked about how in warm air, the molecules expand and with cool air the molecules are closer together. This makes cool air “heavier” than warm air. We read the section in our science book that covered this movement of air and drew pictures for our science notebooks.

For this experiment I had a glass bottle that was cooled in the freezer.  We put a balloon on top and then set the bottle in boiling water.  We were shocked how quickly the balloon shot up and filled with air! In fact, it all made us jump!!

The kids loved this so much that we got out a bowl of ice water and they took turns moving the bottle from the cold water to the hot water and back again. They were surprised how quickly the balloon expanded when they placed the bottle in the hot water, but how long it took to deflate again when placed in the ice water (by comparison).

Visit our other Weather Unit Post:

Clouds, Winds and Weather

• As we started off this unit, we spent quite a bit of time learning about the layers of the Earth’s atmosphere. See more about our Layers of the Atmosphere Packet here:

• Science Experiments about Ice, Blubber and More!

Be sure to check out our other packets:

100 page Earth Science packet:

• Learn how to make a earthquake shake table, hands-on activities to learn about tectonic plate movement, more than a dozen hands-on activities
• Topics include: Solar System, Layers of the Earth, Earth’s Axis and the Seasons, Latitude and Longitude, Plate Tectonics, Earthquakes, Volcanoes, 4 Types of Mountains

• Human Body System Worksheets

• Simple Machines Packet

• Free Rocks and Minerals Packet
• Famous Rocks from Around the World: Free Montessori Cards

Be sure to visit us at our Homeschool Den Facebook page!