Kinetic and Potential Energy Lesson
The teacher I was paired with at the beginning of the semester is a high school Chemistry and Physical Science teacher. Together we developed the idea that we could relate the material to the students' interests if we related energy to the physics of football. Apparently there are new regulations being placed on Oklahoma public school sports regarding concussion injuries. In Oklahoma, most high school students know a football player or two. Bearing this in mind, we concluded that this would make the material relevant to the students. With this I set out designing my lesson.
The purpose of the STEM Outreach class is to introduce engineering students who are interested in education to what it is like to develop a lesson. The lesson we were to design was required to be in 5E format which was new to us because most of us had little to no experience in the role of a teacher. Personally, I had done quite a bit of tutoring at this point, and I taught a Geometry primer for high school students last summer, but I had exactly zero formal training as an educator before beginning this class. My biggest challenge during the development of this lesson was making sure that the material I was putting together was difficulty-appropriate for the students it was being developed for. My classmates, professor, and an educational technology expert on staff at the University all gave me valuable input regarding this. My lesson begins with a slideshow. The first few slides feature images where energy is present in the sense being discussed. The students are to discuss and point out where energy exists in the images and note what form it exists. This is intended to get them in the right mindset and used to spotting energy. Following this discussion is the introduction of the formal definition of energy in terms of work, which the students should already be familiar with. After the formal definition has been thoroughly introduced the students are to begin their first activity. In the first activity, the students choose a few ordinary classroom objects. The students are to lift these objects noting how difficult each is to lift. The students should then weigh the objects they chose and calculate how much energy it requires to lift their objects a certain distance. These calculations should be recorded in a provided table. The students should then calculate how much kinetic energy their object will have when it hits the floor from a fall from the height they lifted their object to. The thing that the students should notice here is that the potential energy their object had before its fall is exactly equal to the amount of kinetic energy it had when it reached the ground. The main idea of this first activity is that students achieve a qualitative understanding of energy quantities and that there is a constant flow of potential to kinetic energy and kinetic to potential energy.
During the second activity is where engineering practices are introduced. In this activity, the students will design helmets to absorb impact energy from a fall. To simulate a human head, the students will be given playground balls and plush material supplied by the instructor to act as padding. Students are to start the activity by dropping their unprotected head analog from a height of 2 meters. This step requires at least two students. One student is to drop the ball and another is to measure how hight he ball bounces after impact with the floor. Using the maximum height the ball reached during its return bounce, the students can calculate how much potential energy it has at that point. The difference in the initial potential energy and the return energy is equivalent to the amount of energy that is being lost during impact to factors outside the scope of this activity. Now that the students have measured and recorded control parameters they should begin designing their helmets. Using kitchen sponges, cotton-like crafting material, foam pad, packaging material and the like, students should design a reusable helmet that will absorb as much energy as possible. Once they have affixed their helmet to the ball, the students should perform the drop test from 2 meters again. As before, one student is to drop the head-helmet system and another should measure the maximum height the helmet reaches after hitting the floor. Again, using this return height the students should calculate how much potential energy their head-helmet system has at that point. By comparing the return energy without a helmet and the return height with a helmet, the students can calculate how much energy is being absorbed by their helmet design. Because one of the goals of this lesson is for the students to gain engineering experience, the students should be encouraged to revise their helmet design to improve how it performs over as many iterations as can be allowed by time. A spreadsheet is provided in the lesson materials for the instructor to use that will verify the calculations of their students and plot the performance of the students' designs in the form of a bar graph. Seeing their performance plotted against that of their classmates might encourage competition among groups.
All lesson materials are provided in the links below.
Teacher's Guide: TeachersGuide [655 KB]
PowerPoint: Kinetic&PotentialEnergy [9.35 MB]
Spreadsheet: HelmetDesignSpreadsheet [14.8 KB]
"Work is Related to Energy" Activity: WorkIsRelatedToEnergy [902 KB]
"Helmet Design" Activity: HelmetDesignActivity [297 KB]