As promised, here is a recap of some of the scientific fun we enjoyed this afternoon. Each of these little experiments could be completed in about ten minutes or so, including digging out the supplies from the dark recesses of your kitchen cabinets. As I mentioned last week, all the ideas are inspired by Horrible Harry at Halloween. (<–affiliate link)

Let me be clear: not one of these is groundbreaking science. Each experiment conveys a simple scientific idea, and is also pretty fun. I did these with zero drama from, or safety threat to, my two year old and three and a half year old. Equally, I’ve done them with a classroom full of second graders. They capture some interest, start some good discussions, and let kids see scientific ideas at work. Classroom teachers, you might want to warn parents what you have done, because some of these tend to get replicated at home.

First up: oil and water don’t mix. (I know you’re shocked, but it’s true.)

For this, you need oil, water, food coloring, and a container in which to mix. I used an empty water bottle because I knew that I could cap it securely and let the girls have fun shaking and mixing.

Add some food coloring to the water. We added yellow first, then red, to make orange like Harry’s teacher did. I let the girls shake after each drop, but you could make this move as quickly or as slowly as you needed.

Once shaken, you want to add the oil. I find that you need enough oil for the little people to really see what’s going on. This is not the time to use your imported cold-press extra virgin olive oil that costs $25 an ounce. Stick to the cheap stuff, people.

I let the girls each add a small bit, and then I poured in enough to make it obvious. More shaking ensued at that point. Then, a bit of waiting (maybe 30 seconds) is key, so the kids can see the oil separate from the water and rise to the top. Here is where you explain (if needed) that the oil did not mix with the water, and that no matter how hard you shake the container, the oil will separate. It “floats” on the water because it is less dense.

For a more thorough scientific explanation for older students, keep reading.

Next up: floating and sinking. You need a big container, water, and some things that will float and sink.

For this one, I did have to spend some time explaining to 3.5 year old Bethany that being in the water is not the same thing as floating… I used a sponge to show how something floats on top of the water. A sheet of paper would also work for this.

Basically, you put things in the water, and see what happens. There might be some surprises, as Harry shows so well in the book. Equally, there are some things that are not surprising at all. If you do this with preschoolers, be prepared that it will devolve into water play. If that’s not going to work for you, then stay vigilant, and empty the tub as soon as you’re done sinking and floating.

This was a fun one. The little pot will float, despite its size, since it’s empty. Bethany had fun adding other objects to the pot to see how much it could hold before it started to sink. Here, it’s important to avoid over-explaining. Just letting her explore was my goal. This was not an AP Physics lesson.

Last, but certainly not least, the grand finale.

For this, you need a plastic pumpkin, water, and a space big enough to swing your arm.

Fill the pumpkin with water.

Straighten your arm, and swing it all the way over your head in a circle. AS LONG AS YOU KEEP IT MOVING, the water will stay inside the pumpkin. The straight arm is key. Don’t be afraid, but equally don’t try this if you’re afraid that the area around you will be ruined if it gets wet. (Take a lesson from what happens when Song Lee gives it a try in our story…)

Here I am mid-swing. You can see by Clara’s reaction, and Bethany’s excellent photography, that we were all having some fun. Depending on your students’ age, you might want to explain that centripetal force is at work. {For more than you ever thought you wanted to know about centripetal force, try this.}

This is really a crowd pleaser, especially in a classroom full of students who are not used to seeing their teachers do crazy things. It’s fun, too, to see your mother swinging a pumpkin around like a nut in the front yard.

If you try these, I’d love to hear the reactions of the little ones in your life!

For more great book suggestions, just click on the picture below.