Over the last few weeks in my math class that focuses on Geometry in the classroom has been exploring measurement. We have had some challenging conversations to say the least, as we were given activities that asked us to measure and we quickly realized much more assumptions are made in measurement than we remembered. These activities were meant to strengthen our core measurement ideals as well as finding ways we can create a lesson that challenges and strengthens the student’s fundamental measurement skills as well.
A key question that needs to be addressed before any measuring was done is why do we need these measurements? This is a foundational thought that teachers need to address before we even start measuring so that students realize that what they are doing has purpose and is used for accurately communicating to other people. Whether that amount is time, or length is up to the specific problem, but we are always asking “How much?”
One activity that we did that I thought was beneficial was we were told to measure the length of the hallway. We were given a tape measure and told that we were to use our stride length in order to determine our length. To start off, when we were told to measure our stride, my group decided that it might be best to find the length of 10 strides, then divide by 10 in order to get the average length, since each stride length could be slightly different and we could use the average. Next we started at one end of the hallway and walked to the corner where the other hallway started. After doing this we multiplied our stride length in centimeters by the number of steps that we got in the hall to find out the length of the hallway.
After finding our hallway lengths and as we began to talk about the vast differences in we were seeing in each-others data, one thing that we realized was that we did not come up with an agreed upon starting and stopping point for how we would measure the hallway. Some of us started at the corner and measured to the next corner while others were measuring wall to wall. Another aspect of measurement that we began to discuss was what an appropriate range for error would be for each of our measurements. This was an interesting concept to begin to talk about as many in the classroom, especially those with little science background were unsure at what an appropriate error would even look like for a problem like this.
By doing this problem in this way, my classmates and I were able to be in the shoes of the students that we will someday be teaching and were able to come across some important questions that students need to ask themselves and understand in order to measure proficiently. Where is the starting and stopping point? How do I use the tool that I have to measure properly? Am I measuring the same way that it was intended to be used to measure? These are all questions that students need to ask so that they are measuring accurately. I think that this lesson did a good job at doing that and I think that it could be adapted so that students could go through the same process. By giving them the guidance of a worksheet that could help them walk though these steps and discover that these are important things to be doing the same so that we all get the same measurement. The worksheet below was created with this purpose. First off, I wanted to give the students a reason to measure. However, the goal of this worksheet is really to focus in on step five where they find their differences. In seeing these differences students will be able to see the importance of starting and stopping in the same place, walking in a straight line and using the tools they have correctly. Ultimately, by learning through inquiry in this way students could have a lasting understanding of measurement and how it can and should be done correctly.