Bouncing, Balloons, and Balance

Gravity is easy-peasy to study.  We dropped things.  And jumped off things.  And bounced balls.  And watched my new favorite SchoolHouse Rock! song & video about gravity.  (Goblin LOVES this song and made us listen to it over and over for days!)  We also briefly discussed 2 physicists who are part of the history of our understanding of gravity, Galileo and Isaac Newton.  The kids colored a picture of Isaac Newton from Color Me Physics  (I'm saving the Galileo page for when we get into astronomy).

Although the kids had a BLAST jumping around the house and dropping everything they could find, the real fun came when we investigated an object's center of gravity.  We took a balloon and filled it with water (you can use a water balloon if you prefer, I found it worked just fine with a regular balloon I had on hand), then tied it off.  We put that balloon INSIDE of another balloon, which I blew up like normal.  (The tricky part was getting the water-filled balloon into the empty balloon, so I enlisted help from Athena.)

Here's what it looks like when you're ready to play (with the light behind it, you can see the smaller water-filled balloon inside your standard balloon:

The balloon filled with water moves around inside the balloon filled with air, changing its center of gravity-- and making for some fun crazy games!  (FYI, our first balloon popped-- not the water one, just the outer one--after the kids took it outside, so we quickly made another.)  For our basic demonstration, I just had the kids toss it back and forth between them, noticing how hard it was to make the balloon move in the direction they wanted.  (We also blew up a balloon-- without putting a false center of gravity inside-- to use as a comparison.)  Afterward, the kids came up with their own ideas of how to play with the balloon, which was awesome to see.

Finally we discussed how an object's center of gravity affects its balance.  We tried to balance quarters on top of pencils, then added forks on either side to create a larger center, making it easier to balance.

Our physics kit also included this goofy clown balancing on his nose.  We attached a few paperclips to the hands and balanced him on a pencil too.  Goblin really liked this guy, so he decided to try to balance it on his nose-- mission accomplished!

Every good science lesson needs to be recorded in journals.

I love seeing their pictures and hearing their explanations.  When they understand what they've learned, it is very simple and to the point, and you can always tell what makes an impact.

--Little Miss Crazy