We recently found a fun book full of simple experiments at the thrift store.  The kids were super excited to come home and try some of them out.  The first experiment they wanted to try showed how expanding and contracting works.  I think that the title Shooting Water Experiment, is what caught their eye:)

Disclaimer: before your kids get too excited, there is not going to be any fire hose action during this experiment.  I think that was what my kids were expecting!  Ha!  But I will say that this is a fun experiment that is great for showing kids how expanding and contracting works.

To set up your own Shooting Water Experiment, you will need:

• Large clear glass container
• Glass bottle with a plastic screw on cap
• straw
• Drill with a bit the same size (or just bigger) as your straw
• Modeling clay or play dough
• Food coloring
• Water
• Safety Pin

Drill a hole in the plastic cap.  I had my hubby do this step for us.  Take the necessary precautions and please be careful.  If you don’t have a drill, you could try using a pair of scissors. 

Fill the bottle halfway with water (we used room temp).  Add a few drop of food coloring to the water and replace the cap onto the bottle.

Place the straw into the hole and form your clay around it to form a seal.  Also place a small piece of modeling clay (or play dough) into the end of the straw.

Place the filled bottle into the glass container and fill the container with HOT water.  Slide a safety pin into the clay at the top of the straw.

Soon you will notice the color water traveling up the straw.  It may take a few minutes before anything happens, so be patient.  When the water is almost at the top of the straw, remove the safety pin.

When the colored water reaches the top, it will begin spurting out like a mini fountain.

The kids thought it was a pretty cool experiment, although I think that the name is a little miss leading.  I think they were expecting to create a giant fountain:)  Ha!  They were on Skype with their Grandparents while they were trying this experiment out.

The mini fountain occurs because the hot water in the bowl warms the air in bottle.  As the air warms up it expands causing the water to be pushed up the straw and eventually creating a little fountain.  This experiment might not have the wow factor that the kids were looking for, but it still is a great way to teach about expanding and contracting.

If you are looking for more experiments to try with your kids, check out this fun list of experiments!