Human Conics: Parabolas
Lesson 7 of 13
Objective: SWBAT define parabolas as a locus of points, apply locus definitions to draw conic sections, and collaborate with partners to solve a problem.
Overview: This lesson is adapted from the Human Conics lessons from the NCTM illuminations website. Check out the lesson on the NCTM site for more details on the lesson. This is our second day on this lesson so we will just be completing the section regarding parabolas.
Preparation: For this lesson, students will need sidewalk chalk and a rope (one piece, 10-12 feet long per group of 3 students).
Narrative: At the start of class, I am going to present the definition of a parabola. Using color to highlight DA and FA and showing that these segments must always be equal. I am not planning on giving students a copy of this definition. I will present the definition using the document camera. I will take a copy of the definition outside in case any teams want to reference it while we are out there.
Students can complete questions 1-2 on their Human Parabola handout before we head outside.
Human Conics: Parabola
Once we are outside, students will work in teams of three to complete the tasks on the Human Parabola handout. They will need to apply the definition of a parabola in order to draw a parabola accurately with sidewalk chalk. I will be checking in with teams and insuring their drawings are accurate. If students don’t seem to be progressing, I may lead a whole class drawing together. Then have students break apart in their teams to draw their own.
I think this activity is going to be challenging for students to figure out how to work as a team to draw the conic sections. I am guessing there are going to be a lot of great student conversations going on. So I want student to focus on Mathematical Practice 3: Construct viable arguments and critique the reasoning of others.
Closure: Class Huddle
With about 5 minutes remaining in the class period, I am going to call students over to a huddle outside. I just want to collect student work now and also ask some closure questions of the class. Here are the questions I will pose to students:
- How many people minimally did it take to draw a parabola?
- What would happen if the rope was longer? Shorter?