Learning about Polygons: First Lesson with Scratch

After being introduced to the fundamentals of how to give commands using a whiteboard, the students were ready for Scratch. The math concept that I was focusing on was how to calculate the exterior angles of a polygon. I wanted students to understand that if they divide 360 by the number of sides in a polygon they would find the exterior angle of the polygon. 

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I could have had students draw various shapes with their protractors but I liked the idea of using Scratch because I knew it would not leave room for any mistakes. The students would have to be exact with their commands otherwise the program wouldn't create the shape they hoped for. I taught the students the basics of how to pull commands in to Scratch, what a sprite was, how to put pen down and how to make the cat move. Then I told them to draw a square using Scratch using the pen down command. A simple code for that would look similar to this.

Once students could show me that they successfully drew a square I challenged them to draw other polygons. This required them to know the degrees of each polygon. The students weren't allowed to use the internet to figure out the angles so most of them guessed and checked on Scratch until they figured it out. While they were doing this I had them record their findings in the table below.  

As students worked on this assignment they demonstrated understanding of polygons. One student (see video below) told me "Ms. Mindy, I figured out how to draw every shape." He then went on to explain the rule that I was hoping students would discover. Every student demonstrated increased understanding of angles and polygons. When I later explained the rule to the class they were easily able to apply it. 

Some of my big take aways from this lesson were:
* The class was very motivated and excited to use Scratch.
* In this case I feel Scratch was a better option than paper and pencil because it self tested as they went and allowed them to make more discoveries.
* It was very easy to differentiate.
* The students didn't need a lot of explanation to get started with Scratch.

Below is a video of two of my students explaining their discoveries. I have also attached a couple of student reflections from this assignment below the video.