As high school teachers, we know that understanding how measurement works is crucial for lab skills and for understanding significant figures. We think measurement should be an easy topic for students to learn; especially because we know that teachers begin working with students in elementary school to teach these skills. However, I, and many other teachers, have spent countless hours teaching and reteaching a seemingly simple skill.
In an effort to implement the science and engineering practices of the NGSS, I have tried to introduce argumentation as a practice into my chemistry courses. I share some growing pains and what I have learned through the process in this blog post.
My first experiment involves measuring the density of water. Each group of two kids is assigned a specific volume of water from 10 to 100 mLs on the tens. They simply measure the mass of an empty graduated cylinder and then add the water and find the mass again. Once they have their data they go around the room and find another group that has one of the volumes that they need and get the data from them and record their names. Once complete they generate a graph of the data and answer a few simple questions. The whole procedure can be completed in about 20 minutes.
Although many students have been exposed to the concept of density before reaching my Chemistry class, I always start the year with this POGIL-like activity.