Classifying Polygons
I.SectionObjectives
- Define polygons.
- Understand the difference between convex and concave polygons.
- Classify polygons by number of sides.
- Use the distance formula to find side lengths on a coordinate grid.
II.ProblemSolvingActivity-PolygonSort
- This activity requires students to sort polygons in three different ways.
- According to whether or not it is a polygon
- Convex or concave
- According to the number of sides
- To prepare this activity, you will need to create or copy different polygons. You want an assortment of polygons
and non- polygons, convex polygons, concave polygons and regular polygons (i.e. quadrilaterals, hexagons,
etc.). Then you can place these all around the room. - When students begin the activity, they need to hunt for a specific number of figures. You could have each
student find three different ones to work with. Then they can choose one for each exercise. - Then you can do a sorting exercise.
- For example, “All of the polygons sit down. All of the non- polygons stand up.”
- Then you can ask for a few examples from each group to explain why they are or are not a polygon.
- Next, you can do another sort. Concave figures to the front of the room. Convex to the back of the room.
- Same thing- ask for students to demonstrate why the figure is concave or convex.
III.MeetingObjectives
- Students will be required to define polygons.
- Students will demonstrate an understanding between concave and convex polygons.
- Students will classify polygons according to the number of sides.
IV.NotesonAssessment
- Assess student understanding by checking each “sorting exercise”
- Also ask different student for feedback about why they “sorted” their polygons the way that they did.
- Allow time for feedback and student questions.
Problem Solving in Geometry
I.SectionObjectives
- Read and understand given problem situations.
- Use multiple representations to restate problem situations.
- Identify problem- solving plans.
- Solve real- world problems using planning strategies.
II.ProblemSolvingActivity-CampingFireExpansion
5.1. Basics of Geometry