A few months ago, after a full year of home schooling Christopher, I decided that I finally felt comfortable with our routine to host learning sessions. Since I have a science degree, and I enjoy hands on learning, I decided that perhaps hosting a Science Club would be a good fit for me. I made sure that there was interest among my local homeschool group (which also happens to be a group of my close friends), did some research on science clubs, started a science board on Pinterest, joined a few yahoo groups for science educators, and outlined a few experiments that I thought we could cover over the year. There is a wealth of information on science experiments on the internet, not to mention thousands of videos of experiments and science classes on youtube, however, some of them don’t have a lesson plan or lab report to help assist in applying what you see during the experiment with the supporting scientific principles. Furthermore, without a lesson plan to accompany the experiment, it’s more of a “Wow, what’s happening there is really cool” moment, rather than the “Aha!! I understand WHY that happened” moment that I’m hoping to achieve. It’s not enough that the experiments be visually exciting, not with the middle schoolers that I hope to help learn. I want the principles of science to be reinforced as well.
But that doesn’t mean that the really great experiments that I’ve come across can’t be used. It just means that I have to do some work to plan the lessons and to devise the lesson plans (I don’t mind sharing, so I’ve included the links below). This month’s meeting expanded on our study of mass, density, volume, and buoyancy. Having been inspired by this pin, and having checked out the source blog, I decided that our lab would involve a study of the above principles as related to bars of soap. Naturally, I made sure that Ivory soap was included among our test subjects. I mean, check out the blog, especially the video. Who WOULDN’T want to see that?!
All of the participants brought two matching bars of another brand of soap of their choosing (to encourage thinking along the lines of how to assess the reliability of data). We began by determining mass using a regular kitchen scale. Then we compared the results of our volumes by using math equations vs. fluid displacement measurements. Once we obtained the volumes, we calculated density and predicted which soaps would float (hypothesizing that soaps with a density of less than 1.0 g/cubic centimeter would float, seeing as how the density of water is 1.0 grams/cubic centimeter). We learned the most soaps immediately sink when submerged in water. We also learned that careful measurement and calculation of volume was crucial to the reliability of our data, and how even a tiny error in calculations can throw off the validity of an entire data set. If you are interested, the lab that we used is here, and the chart that we used to track our data is here.
Good old Ivory soap, it indeed floated. That gave me the opportunity to give my explanation (I explained Archimedes’ principle and told the kids about how Ivory soap is whipped fluffy with air during the manufacturing process, thereby decreasing its density, and making it buoyant). Then I led the kids a bit further until they remembered Charles’ Law from an earlier lesson, at which point, I segued into performing the experiment from the source blog. I offered to heat the bar of Ivory in the microwave, to help the group determine if its volume would increase, as Charles’ Law indicated that it should . And in two minutes, it went from this:
You want to talk about some excited kids? You should have heard their squeals as we watched the soap puff up like a cloud in the microwave. They were giddy, but more importantly, they understood WHY this result occurred. This is a pretty clear visual application of Charles’ Law, and that point was hammered home with this bunch. They’re sharp kids, anyway, of course, so I’d expect nothing less, but I seriously doubt they’ll be forgetting Charles’ Law anytime soon. I know I won’t be.
Learning need not be expensive, or flashy. In this case, all it took was some soap and a microwave for a good, clean lesson in Charles’ Law, with a side of mass, volume, density, and buoyancy.
(Stay tuned for an upcoming about what we did with our foam when we were done with this experiment! The source blog is an amazing resource, I can’t wait to tell you all about it!)