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Grade 2 (age 7-8)

Shapes Classification

Shapes Classification

All around us hide shapes like triangles, quadrilaterals, and circles. A roof is a triangle, a window is a quadrilateral, and a coin or pizza is a circle. You can tell them apart by counting corners and sides: a triangle has 3 of each, a quadrilateral has 4, and a circle is round with none. Here you pick a shape to study its vertices and sides, then hunt for shapes in everyday objects.

Shapes Around Us
👀 Shapes are Everywhere!
①Roofs are triangles, windows are quads
②Coins and pizzas are circles
③Look around — shapes everywhere!
Properties of Shapes
0
💡 How to Tell Shapes Apart
①Triangle: 3 vertices, 3 sides
②Quad: 4 vertices, 4 sides
③Circle: no vertices/sides, round
Finding Shapes in Life
0
🏠 Where to Find Them?
①Triangles: roof, set square, traffic sign
②Quads: books, windows, chalkboards, doors
③Circles: clocks, coins, wheels, plates
Summary
Triangle
3 vertices + 3 sides = Triangle
Surrounded by 3 straight lines
Quadrilateral
4 vertices + 4 sides = Quadrilateral
Surrounded by 4 straight lines
Circle
0 vertices + 0 sides = Circle (round)
Set of points at equal distance from a center
🎯 Remember!
①Vertex: where sides meet
②Side: line connecting vertices
③Triangle has 3, quad has 4
④Circle has no vertices/sides
⑤Practice finding shapes around you!
Examples and Unit Test
Example 1
What is the name of a shape with 3 vertices and 3 sides?
1
Tell shapes apart by their number of vertices and sides.
2
A shape with 3 vertices and 3 sides is a triangle.
▸ Triangle
A triangle has 3 vertices and 3 sides.
Example 2
How many vertices and sides does a quadrilateral have?
1
A quadrilateral is a shape surrounded by four straight lines.
2
It has 4 sides, and the vertices where sides meet are also 4.
▸ 4 vertices, 4 sides
In a shape, the number of sides equals the number of vertices.
Unit Test
Which shape is round with no vertices and no sides?
①triangle
②quadrilateral
③circle
④pentagon
▸ ③ circle
1
A circle is made of a round curve.
2
A circle has no straight sides and no vertices at all.
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Multiplication Table
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Length Measurement