Today I was so busy having fun that I put off working on this week's experiment. I had several ideas bubbling around in my brain, but nothing quite came together. Then, as I often do when I am looking for an idea, I picked up the first thing I saw and began playing with it. It happened to be a bottle of liquid soap. I turned it over and watched as the bubble rose slowly through the thick liquid. I knew that I had this week's experiment. You will need:

Newton's Laws

This time we will investigate Newton's laws of motion. While Galileo laid the foundations for them, Newton was the one that put them into the form that we know them today.

Fish in a Bucket

This week's experiment goes back to fishing trips from my childhood. As we caught fish, we put them into a large tub of water. I loved watching them swim around and around. I was told that if you weighed the tub, that it would not register the weight of the fish, unless they touched the sides or bottom of the tub. Was that right? Let's find out.

Making a Density Column

This experiment is one of the classics that is still a lot of fun to play with. It has to do with density. Density can be a difficult concept to grasp, but it is much easier once you have played with a density column.

Imagine that I have three cups that are the same size. If I fill one cup with water, one with sand, and one with lead. Would they all weigh the same? No, of course not. A cup of sand weighs more than a cup of water. Sand is denser than water. Lead is denser than sand, so a cup of lead weighs more than a cup of sand.


Bowl of water on scale
I weighed this bowl of water. If I stick my hand in the water, and weigh it again, will it weigh more? If so, how much more. If not, why not?


Running horse
Running horses played an important role in the development of a very common, modern technology. What is it?

Pine Cone Weather

Back in the dark ages, when I was in school, we used human hair to construct a hygrometer for measuring the humidity in the air. Since hair counts as "human tissue", many schools are not able to make hair hygrometers, but you can build a nice hygrometer using a pinecone instead of a hair.

To do this, you will need: