Density and Measuring

If you are looking for a measuring and density activity that will be challenging, allow students to experience success early on and can be boxed up to use again, you might consider trying the activity that I am sharing in this post.  

Balancing Equations with Molecular Models

I am a very firm believer that the world of physical science can be visualized and is an excellent medium for teaching students to model and to picture what happens at the molecular level. The first topic we decided to explore was balancing chemical equations. This seems like such a simple topic to chemistry teachers but I have found that it can be quite challenging for many of my inner city students. The first thing they ask me for is a list of rules that they can follow. We can discuss the problems of algorithmic teaching in a later post! For the time being let’s talk about how to get students to understand why they need to balance equations and discuss what we can call “Conservation of Atoms”.

Time required: 

50 minutes

Making Measurement Meaningful or Why to Avoid Saying "Sig Figs" in Class.

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.