Early Math · Grade K
Shapes Around Us: Flat and Solid
Quick answer
Shapes have names: circle, square, triangle, rectangle and hexagon are flat, and cube, cone, cylinder and sphere are solid. A shape keeps its name when it is turned, moved, or made bigger or smaller, because its sides and corners do not change. Things in the world have these shapes too — a ball is a sphere and a can is a cylinder — and words like above, below, beside, in front of, behind and next to tell where they are.
What you'll learn
- Name circles, squares, triangles, rectangles and hexagons of any size, facing any way
- Tell flat shapes from solid shapes, and name cubes, cones, cylinders and spheres
- Use above, below, beside, in front of, behind and next to
Flat shapes
Here are five flat shapes. Each one has a name.
A circle is round. A square has sides, all the same length. A triangle has sides. A rectangle has sides, two long and two short. A hexagon has sides.
A flat shape lies on a page, like a drawing. You can not pick it up.
Solid shapes
These shapes are solid. You can hold them in your hand.
A block is a cube. A party hat is a cone. A can is a cylinder. A ball is a sphere.
Why a turned shape keeps its name
Look at all these triangles. Some are big. Some are small. Some point up and some point down.
Each one has sides and corners. So each one is a triangle.
Turn a shape and it still has the same sides and corners. Make it bigger and it still has them too. A shape’s name comes from its sides and corners. It does not come from how it sits or how big it is.
Where is it?
Some words tell where a thing is: above, below, beside, next to, in front of and behind.
The ball is above the box. The box is below the ball. The cone is next to the box. You could also say the cone is beside it.
Hide a toy behind a box. Now the box is in front of the toy.
Worked examples
Common mistakes
Practice problems
-
What shape is this?
What shape is this? Answer
A hexagon
Full solution
It has sides and corners. It is turned, but it is still a hexagon.
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Is a ball flat or solid?
Answer
Solid
Full solution
You can hold a ball. It takes up space. A ball is a sphere.
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What solid shape is a can like?
Answer
A cylinder
Full solution
A can has a round top, a round bottom and a curved side. That is a cylinder.
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How many triangles are here?
How many triangles? Answer
Full solution
The first, third and last shapes each have sides. The square and the circle are not triangles.
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A party hat is shaped like which solid?
Answer
A cone
Full solution
A party hat has a round bottom and comes to a point at the top. That is a cone.
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Is a drawing of a square flat or solid?
Answer
Flat
Full solution
A drawing lies on the page. You can not pick it up, so it is flat.
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Where is the cube?
Where is the cube? Answer
Above the cylinder
Full solution
The cube is on top. So the cube is above the cylinder, and the cylinder is below the cube.
-
Name a thing that is shaped like a rectangle.
Answer
A door, a book or a window are some answers.
Full solution
Any thing with sides, two long and two short, and square corners works.
-
A small square and a big square sit side by side. Are they both squares?
Answer
Yes
Full solution
Size does not change the name. Both have sides the same length and square corners.
-
Sam sees a triangle that points down. He says it is not a triangle. What went wrong?
Hint
Count its sides.
Answer
It is still a triangle. Turning it does not change its sides.
Full solution
A shape’s name comes from its sides and corners. This shape has sides and corners.
So it is a triangle, no matter which way it points.
Frequently asked questions
What shapes do kindergartners learn?
Flat shapes: circles, squares, triangles, rectangles and hexagons. Solid shapes: cubes, cones, cylinders and spheres.
What is the difference between flat and solid shapes?
A flat shape lies on a page, like a drawing. A solid shape takes up space and can be held, like a ball or a box. Flat shapes are also called 2D, and solid shapes 3D.
Is a square turned on its corner a diamond?
It is still a square. It has 4 sides the same length and 4 square corners, and turning it does not change them.
What are position words?
Words that tell where something is: above, below, beside, in front of, behind and next to.
What shape is a ball?
A sphere. A circle is flat, like the outline of a ball drawn on paper, but the ball itself is a solid sphere.
Standards alignment
This lesson covers the following Common Core State Standards for Mathematics.
- CCSS.MATH.CONTENT.K.G.A.1GeometryDescribe objects in the environment using names of shapes, and describe the relative positions of these objects using terms such as above, below, beside, in front of, behind, and next to.
- CCSS.MATH.CONTENT.K.G.A.2GeometryCorrectly name shapes regardless of their orientations or overall size.
- CCSS.MATH.CONTENT.K.G.A.3GeometryIdentify shapes as two-dimensional (lying in a plane, "flat") or three-dimensional ("solid").