Every year when the day came to discuss the rules for significant figures in measurements with my classes I would write the rules on the board, we’d work through a couple examples, and I’d try to find a way to explain why we needed to use them when reporting measurements. This has never been my favorite topic to teach, mostly because I had a difficult time helping students see why these rules for measurement and reporting uncertainty were important.
In this Activity, students collect data outdoors on a rainy day using plates and paper towels and use the information to calculate the rate of rainfall. This Activity reinforces ideas about density, mass, volume, area, length, and units.
Whenever possible, I try to begin a topic with something my students are familar with. For the introduction of Percent Composition in my general chemistry course, I brought in bags of Oreo cookies. Seeing the bags upon entering class was a great attention getter. If you are looking for ways to add more inquiry to your chemistry course, this a an example of how you can experiment with giving up a little control. Try it and see how it goes.