Measurement of Interior Angle
Students can begin this unit by doing some of the intermediate to advanced activities in Code.org which introduces the drawing blocks and geometric programming. Alternatively, start with the Hook Activity in the following Lesson Flow - Polygons
Lessons on Polygons Using A Big Ball of Yarn.
2 Direct Instruction
Direct instruction begins with a teacher lead Q and A.
Have the students identify the coordinate grid system: the lowest (x,y) values, the greatest (x,y) values.
Demonstrate how to program Scratch to draw a square using the coordinate grid. This familiarizes students with the drawing code blocks in Scratch, their functions, and the coordinate grid system in Computer Science. Think video games.
Continue with student exploration.
Have students work independently or in pairs to program Scratch to create an equaliateral triangle and a square that are equvalent to the base and height of the demonstrated square.
Exit Ticket: What are the other drawing possibilities using the coordinate grid system of Computer Science.
3 Guided Practice
4 Independent Practice
Using their knowledge of the Pen code blocks in Scratch and the coordinate grid students use their responses to the column "Scratch Programing Angle" on the Google chart above and program Scratch to draw five polygons using only the move and degrees block from the Motion (blue section) in Scratch Code.
Advise students to use the pen up and pen down code blocks as they begin and end their polygons around the coordinate grid.
Polygons cannnot overlap.
Polygons touching the edge will not work or complete succesfully.
Students have to keep their polygons small - perhaps moving no more then 60 steps.
Grade students on the chart, the drawing shapes using the coordinate grid and drawing the five polygons using the move and degrees blocks. A follow up to this will be for students to enter different values from the chart to the degrees block in Scratch. Suggest for students to use the actual value from the degree of the interior angle of the Polygon. What happens? Does it draw the polygon? What does it draw? Why do you think so? Can a programmer use this value or the sum of the interior angles to have Scratch draw polygons?
Exit Ticket: Have students Identify the curricular connections using their math text books.