Polygon names poster (free printable sides chart)

About this sheet

A polygon is a closed flat shape made of straight sides, and its name tells you how many it has. Tri means three, quad means four, penta five, hexa six, and so on up to deca, ten. Once children notice that the front of the word carries the count, they can work out a name they have never heard. This poster lists eight polygons from three sides to ten, each name on the left and its side count on the right. There is room beside each line for a sketch, which turns the chart into something the class finishes itself. Because every line is editable, you can stop at the hexagon for younger children or add the dodecagon for older ones.

Grades: 2 to 5.

How to use it

1. Check the eight rows, trim or extend them to match the shapes your class has met, and keep each count with its name.
2. Print the poster and mount it near the pattern blocks and the geoboards, where shapes are built and named.
3. Challenge children to make each shape and count the sides aloud, and then to find one in the room or on a picture.

Five ideas for class

1. Stretch a band around pegs on a geoboard to build a pentagon, then a hexagon, and ask what changed when you added one peg.
2. Go on a shape walk and photograph or sketch a stop sign, a window and a tile, then match each to a name on the chart.
3. Ask children to guess a polygon from its prefix: what might octo mean, given an octopus has eight arms? Then check the poster.
4. Draw a regular hexagon and a lopsided one side by side, and agree that both are hexagons because the side count, not the look, gives the name.
5. Play a clue game: I have seven sides, and I am closed. Who am I? Children answer with the name and then draw it.

Related

• Dot paper
• Pattern blocks
• Geoboard