Identifying Shapes (basic)
There are several stages to identifying shapes (and classifications can often become more and more specific).
The first set of shapes that students typically learn are two-dimensional or plane shapes (they have only two dimensions: length and width and occupy a plane).
Plane shapes are made up of lines and vertices (a vertex is a corner, where more than one line meet). Polygon is the general name for a "many sided" shape.
The first common shape is not a polygon, because it's made with just one line (and so no vertices), a circle:

The rest of the common shapes are identified first by number of sides and vertices and, in the case of squares v. rectangles, whether or not those sides are equal.
| Triangle | Rectangles (not equal sides)/Squares (equal sides) | Pentagon | Hexagon | And so on.... |
| 3 sides/vertices | 4 sides/vertices (quadrilaterals) | 5 sides/vertices | 6 sides/vertices | Septagon = 7 sides Octogon = 8 sides Nonagon = 9 sides Decagon = 10 sides |
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See additional lessons for more shapes: Identifying Quadrilaterals, Identifying Triangles by Sides, Identifying Triangles by Angle, Identifying 3-Dimensional Shapes.



