Implementing Unit Conversions Through Dimensional Analysis
Summary
We hope that getting students out of their desks in the math classroom and into the gym to record their personal speeds will provide some real world motivation to use the dimensional analysis process to compare their speed with Usain Bolt, the fastest man in the world.
CollapseLearning Goals
Students will implement dimensional analysis to convert their own running times from feet per second to miles per hour and Usain Bolt's time running 100 meters in 9.69 seconds to miles per hour so they can make a comparision between the two times.
Students will gather class data and organize and present their findings using the central tendency tool: box and whisker plots.
Context for Use
This lesson was taught to 8th graders in Mabel and Lanesboro, very small communities in SE Minnesota. The Mabel 8th graders are a nice, hard-working group, but are not wiz kids. In Lanesboro, there are a few students who are very difficult to engage in the learning process. Each class is comprised of 20-24 students.
Prior to this lesson, a day was spent introducing dimensional analysis. Central tendency skills were taught last year and in previous units this year.
The day after this lesson, central tendency reporting would be presented by the students.
Description and Teaching Materials
See attached materials: Lesson Plan, Student Form, Homework and Additional Worksheets.
Lesson Plan Dimensional Analysis (Microsoft Word 2007 (.docx) 12kB Jun4 09)
Dimensional Analysis Student Form (Microsoft Word 2007 (.docx) 16kB Jun4 09)
Dimensional Analysis Homework (Microsoft Word 2007 (.docx) 17kB Jun4 09)
Dimensional Analysis Additional Worksheets (Microsoft Word 2007 (.docx) 399kB Jun4 09)
Teaching Notes and Tips
The important thing to remember in this activity is that we want students to be willing participants. You may be lucky enough to have a class full of students who all want to run and make their best time possible. But most likely you will have some students who don't want to run. That is fine. Encourage them to walk, skip, jog, or cover the required distance in any way possible so they can get a personal time to convert.
Also, if you are planning this lesson during nice weather, you will get a greater variety of times if you use a longer distance than you can cover in a gym. It makes the central tendency reporting more interesting.
Most likely you will fill up the class period with the opening Usain Bolt conversion problem, recording student times and converting student times to miles per hour. Hopefully your brightest students will get to the box and whisker plot by the end of class and will be willing to present class data at the beginning of class tomorrow.
Assessment
Are students doing their own conversions or are they relying on others to do it for them. Does each student's mile per hour rate make sense? Do students remember how to create a box and whisker plot? Do students compute unit conversions correctly on homework worksheet?