Properties of Shapes — Grade 1 Mathematics
Shapes are everywhere — in the windows, wheels, books, ice cream cones, and tin cans around you. In Grade 1, we identify and describe 2D (flat) shapes and 3D (solid) shapes by counting their sides, corners (vertices), and faces. Understanding shapes is the foundation of geometry!
Key Shape Words
Side (Edge) — a straight or curved line that forms part of a shape's boundary.
Corner (Vertex) — a point where two sides meet.
Face — a flat surface on a 3D shape.
2D shape — flat, like a drawing on paper (length + width only).
3D shape — solid, takes up space (length + width + depth).
Corner (Vertex) — a point where two sides meet.
Face — a flat surface on a 3D shape.
2D shape — flat, like a drawing on paper (length + width only).
3D shape — solid, takes up space (length + width + depth).
2D Shapes
Circle
0 sides · 0 corners
Perfectly round
Perfectly round
Square
4 equal sides
4 corners
4 corners
Rectangle
4 sides (2 pairs equal)
4 corners
4 corners
Triangle
3 sides
3 corners
3 corners
Pentagon
5 sides
5 corners
5 corners
| Shape | Sides | Corners | Real-World Example |
|---|---|---|---|
| Circle | 0 | 0 | Wheel 🎡, coin 🪙 |
| Square | 4 (equal) | 4 | Window pane 🪟, tile |
| Rectangle | 4 | 4 | Door 🚪, book 📚 |
| Triangle | 3 | 3 | Pizza slice 🍕, roof 🏠 |
| Pentagon | 5 | 5 | Home plate (baseball) |
3D Shapes
Cube
6 square faces
8 corners
8 corners
Sphere
1 curved face
No corners
No corners
Cylinder
2 flat circles
1 curved side
1 curved side
Cone
1 flat circle
1 curved side, 1 point
1 curved side, 1 point
Practice Questions
1. How many sides does a triangle have?
✅ A triangle has 3 sides and 3 corners.
2. Name a shape with 4 equal sides and 4 corners.
✅ A square has 4 equal sides and 4 corners.
3. Which 3D shape looks like a ball?
✅ A sphere — e.g., a football or globe.
4. A shape has 5 sides and 5 corners. What is it called?
✅ A pentagon.
5. What is the difference between a square and a rectangle?
✅ A square has all 4 sides equal. A rectangle has 2 pairs of equal sides (opposite sides are equal), but not all 4 are the same.
Key Points to Remember
- 2D shapes are flat; 3D shapes are solid.
- Count sides (edges) and corners (vertices) to identify 2D shapes.
- A circle has no straight sides and no corners.
- A square is a special rectangle — all 4 sides are equal.
- 3D shapes have faces (flat or curved surfaces).