Week 21TuesdayPolygons vs. Non-Polygons
1Warm-up: Vertex Fluency

2-min Fluency Warm-up — Vertices in a flash!

A triangle has vertices.

A square has vertices.

A rectangle has vertices.

A hexagon has vertices.

2Estimate First: How Many Sides?

Estimate First! Glance at each shape for ONE second. Guess how many sides — then count to check.

My guess: Actual count:

My guess: Actual count:

My guess: Actual count:

My guess: Actual count:

3Polygon or Not?

A polygon is a closed shape made only of straight sides. If a shape is open or has curves, it is NOT a polygon. Write yes or no.

Polygon?

Polygon?

Polygon?

Polygon?

Polygon?

Polygon?

4Show Two Different Ways

Show Two Different Ways — A circle is not a polygon. Give two different reasons a shape might fail the polygon test.

Reason 1:

Reason 2:

5Word Problem

Think about what is happening.

Jake drew a shape with 4 straight sides, but he forgot to connect the last side back to the start. His sister says it is a quadrilateral. Is she right? Explain.

My thinking:

Right or wrong?