Shapes
By the end of this chapter you will be able to
- Name a circle, square, triangle and rectangle, even when turned
- Count the sides and corners of a flat shape
- Name a cube, cuboid, sphere and cone
- Sort shapes and say which one does not belong
You should already know
- Counting to 20 (Chapter 2)
- Comparing and sorting (Chapter 3)
Where this leads
- Level 2: counting in ones to 50 and 100, and comparing numbers to 100
Step-by-step practice: maths (Level 1). Small steps, repeated until fluent. Content: Name and recognise circle, square, triangle and rectangle, Say how many sides and corners a 2-D shape has, Name cube, cuboid, sphere and cone in simple pictures, Sort shapes into groups by one property, and say which shape does not belong.
Exercise P Do you remember?
Non-calculatorMethod. Start at 6 and count on 4.
- Start at 6. The bigger number is 6.6
- Count on 4. Seven, eight, nine, ten.7, 8, 9, 10
- Write the answer. 10
Check. 4 + 6 = 10. It is the same both ways.
Watch out. Count on from the bigger number.
Method. Count on one at a time from 16.
- Start at 16. We count on from 16.16
- Say the next two numbers. Each number is one more.17, 18
- Write the answer. 17, 18
Check. Count back from 18 to 16: 18, 17, 16. It matches.
Watch out. Start with the number after 16.
Method. Count on from 8 to 10.
- Start at 8. It is the part we know.8
- Count on to 10. Nine, ten.2 steps
- Write the answer. 2
Check. 8 + 2 = 10. It works.
Watch out. Count on from the known part to 10.
Method. Start at 9 and count back 6.
- Start at 9. This is where we begin.9
- Count back 6. Eight, seven, six, five, four, three.8, 7, 6, 5, 4, 3
- Write the answer. 3
Check. 3 + 6 = 9. It works.
Watch out. Count back, to the left.
Method. Count on from 12 to 14. The number in the middle is between them.
- Start at 12. It is the smaller number.12
- Count on one. Thirteen is between 12 and 14.13
- Write the answer. 13
Check. Count on from 13 to 14. It works.
Watch out. Between means after the smaller number and before the bigger one.
Names of flat shapes
Flat shapes are called 2-D shapes. The four you need first are:
a circle (round), a square (four equal sides), a triangle (three sides) and a rectangle (four sides, two long and two short).
Key ideas
- A circle is round, with no corners.
- A square has four equal sides.
- A triangle has three sides.
- A rectangle has four sides. Two sides are longer than the other two.
- A shape stays the same when it is turned.
Method. Look at the outline. Count the sides.
- Look at the outline. It has four straight sides and four corners.4 sides
- Check it is equal. The four sides are the same length, so it is a square.all sides equal
- Write the name. square
Check. It is a square even though it is turned round.
Watch out. A square turned on its corner is still a square.
Method. Count the sides and corners.
- Count the sides. It has three straight sides.3 sides
- Count the corners. It has three corners.3 corners
- Write the name. triangle
Check. Three sides and three corners make a triangle.
Watch out. Count the sides, not the points at the top.
Method. Look at the outline. Is it round?
- Look at the outline. It is round all the way round.no straight sides
- Check for corners. It has no corners.no corners
- Write the name. circle
Check. A circle is round and has no corners.
Watch out. A circle has no straight sides at all.
Watch out
Watch out. A rectangle can look like a square. Check whether all four sides are the same length.
Exam tip
Grown-up tip. Look for these shapes at home: a plate (circle), a book (rectangle), a tile (square) and a slice of pizza (triangle). Ask: “How many sides?”
Exercise 10A Names of flat shapes
Non-calculatorMethod. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.square
- Check the sides. It has 4 equal sides.4 equal sides
- Write the name. square
Check. A square has 4 corners and 4 equal sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 3 corners.triangle
- Check the sides. It has 3 sides.3 sides
- Write the name. triangle
Check. A triangle has 3 corners and 3 sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 3 corners.triangle
- Check the sides. It has 3 sides.3 sides
- Write the name. triangle
Check. A triangle has 3 corners and 3 sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.square
- Check the sides. It has 4 equal sides.4 equal sides
- Write the name. square
Check. A square has 4 corners and 4 equal sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 3 corners.triangle
- Check the sides. It has 3 sides.3 sides
- Write the name. triangle
Check. A triangle has 3 corners and 3 sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.square
- Check the sides. It has 4 equal sides.4 equal sides
- Write the name. square
Check. A square has 4 corners and 4 equal sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It is round all the way round.circle
- Check the sides. It has no straight sides.no straight sides
- Write the name. circle
Check. A circle has no corners and no straight sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.rectangle
- Check the sides. It has 2 long sides and 2 short sides.2 long sides and 2 short sides
- Write the name. rectangle
Check. A rectangle has 4 corners and 2 long sides and 2 short sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 3 corners.triangle
- Check the sides. It has 3 sides.3 sides
- Write the name. triangle
Check. A triangle has 3 corners and 3 sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.rectangle
- Check the sides. It has 2 long sides and 2 short sides.2 long sides and 2 short sides
- Write the name. rectangle
Check. A rectangle has 4 corners and 2 long sides and 2 short sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It is round all the way round.circle
- Check the sides. It has no straight sides.no straight sides
- Write the name. circle
Check. A circle has no corners and no straight sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.square
- Check the sides. It has 4 equal sides.4 equal sides
- Write the name. square
Check. A square has 4 corners and 4 equal sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.square
- Check the sides. It has 4 equal sides.4 equal sides
- Write the name. square
Check. A square has 4 corners and 4 equal sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.rectangle
- Check the sides. It has 2 long sides and 2 short sides.2 long sides and 2 short sides
- Write the name. rectangle
Check. A rectangle has 4 corners and 2 long sides and 2 short sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 3 corners.triangle
- Check the sides. It has 3 sides.3 sides
- Write the name. triangle
Check. A triangle has 3 corners and 3 sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.rectangle
- Check the sides. It has 2 long sides and 2 short sides.2 long sides and 2 short sides
- Write the name. rectangle
Check. A rectangle has 4 corners and 2 long sides and 2 short sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Sides and corners
A side is a straight edge. A corner is where two sides meet.
A square and a rectangle each have 4 sides and 4 corners. A triangle has 3 sides and 3 corners. A circle has no sides and no corners.
Key ideas
- A side is a straight edge.
- A corner is where two sides meet.
- A circle has no straight sides and no corners.
Method. Trace the outline with your finger.
- Trace each edge. Count each straight edge once.1, 2, 3
- Count the sides. The triangle has three straight sides.3
- Write the answer. 3
Check. The triangle has 3 corners too.
Watch out. Count each edge once. Do not count a side twice.
Method. Count where two sides meet.
- Find each corner. A corner is where two sides meet.top left, top right, bottom left, bottom right
- Count the corners. There are four corners.4
- Write the answer. 4
Check. A rectangle has 4 sides and 4 corners.
Watch out. Count each corner once.
Method. A circle is round, so look for corners.
- Look for corners. There is no point where two straight sides meet.no corners
- Count the corners. A circle has none.0
- Write the answer. 0
Check. Zero corners means none.
Watch out. The round shape has no corners, so write 0.
Watch out
Watch out. Count sides and corners separately. Each corner joins two sides.
Exam tip
Grown-up tip. Trace each shape with a finger and count the edges out loud. Ask: “How many corners?” before you count the sides.
Exercise 10B Sides and corners
Non-calculatorMethod. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.rectangle
- Count the straight sides. A rectangle has 2 long sides and 2 short sides.4
- Write the answer. 4
Check. The number of corners is the same as the number of straight sides for these shapes. ✓
Watch out. A curved line is not a side. Count only straight edges.
Method. Count the corners. A corner is where two straight sides meet.
- Find each corner. Mark each point where two straight sides meet.square
- Count the corners. A square has 4 corners.4
- Write the answer. 4
Check. Count the corners again, one at a time. ✓
Watch out. Count each corner once. The round shape has none.
Method. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.circle
- Count the straight sides. A circle has no straight sides.0
- Write the answer. 0
Check. A circle has no corners and no straight sides.
Watch out. A curved line is not a side. Count only straight edges.
Method. Count the corners. A corner is where two straight sides meet.
- Find each corner. Mark each point where two straight sides meet.square
- Count the corners. A square has 4 corners.4
- Write the answer. 4
Check. Count the corners again, one at a time. ✓
Watch out. Count each corner once. The round shape has none.
Method. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.square
- Count the straight sides. A square has 4 equal sides.4
- Write the answer. 4
Check. The number of corners is the same as the number of straight sides for these shapes. ✓
Watch out. A curved line is not a side. Count only straight edges.
Method. Count the corners. A corner is where two straight sides meet.
- Find each corner. Mark each point where two straight sides meet.square
- Count the corners. A square has 4 corners.4
- Write the answer. 4
Check. Count the corners again, one at a time. ✓
Watch out. Count each corner once. The round shape has none.
Method. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.triangle
- Count the straight sides. A triangle has 3 sides.3
- Write the answer. 3
Check. The number of corners is the same as the number of straight sides for these shapes. ✓
Watch out. A curved line is not a side. Count only straight edges.
Method. Count the corners. A corner is where two straight sides meet.
- Find each corner. Mark each point where two straight sides meet.triangle
- Count the corners. A triangle has 3 corners.3
- Write the answer. 3
Check. Count the corners again, one at a time. ✓
Watch out. Count each corner once. The round shape has none.
Method. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.rectangle
- Count the straight sides. A rectangle has 2 long sides and 2 short sides.4
- Write the answer. 4
Check. The number of corners is the same as the number of straight sides for these shapes. ✓
Watch out. A curved line is not a side. Count only straight edges.
Method. Count the corners. A corner is where two straight sides meet.
- Find each corner. Mark each point where two straight sides meet.circle
- Count the corners. A circle has no corners.0
- Write the answer. 0
Check. Count the corners again, one at a time. ✓
Watch out. Count each corner once. The round shape has none.
Method. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.circle
- Count the straight sides. A circle has no straight sides.0
- Write the answer. 0
Check. A circle has no corners and no straight sides.
Watch out. A curved line is not a side. Count only straight edges.
Method. Count the corners. A corner is where two straight sides meet.
- Find each corner. Mark each point where two straight sides meet.rectangle
- Count the corners. A rectangle has 4 corners.4
- Write the answer. 4
Check. Count the corners again, one at a time. ✓
Watch out. Count each corner once. The round shape has none.
Method. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.rectangle
- Count the straight sides. A rectangle has 2 long sides and 2 short sides.4
- Write the answer. 4
Check. The number of corners is the same as the number of straight sides for these shapes. ✓
Watch out. A curved line is not a side. Count only straight edges.
Method. Count the corners. A corner is where two straight sides meet.
- Find each corner. Mark each point where two straight sides meet.rectangle
- Count the corners. A rectangle has 4 corners.4
- Write the answer. 4
Check. Count the corners again, one at a time. ✓
Watch out. Count each corner once. The round shape has none.
Method. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.triangle
- Count the straight sides. A triangle has 3 sides.3
- Write the answer. 3
Check. The number of corners is the same as the number of straight sides for these shapes. ✓
Watch out. A curved line is not a side. Count only straight edges.
Method. Count the corners. A corner is where two straight sides meet.
- Find each corner. Mark each point where two straight sides meet.square
- Count the corners. A square has 4 corners.4
- Write the answer. 4
Check. Count the corners again, one at a time. ✓
Watch out. Count each corner once. The round shape has none.
Solid shapes
Solid shapes are called 3-D shapes. They have depth as well as width and height.
A cube has six square faces. A cuboid is a box with flat faces. A sphere is round like a ball. A cone has a flat round base and a point.
Key ideas
- A cube has six square faces.
- A cuboid is a box shape.
- A sphere is round and has no flat faces.
- A cone has a point and a round base.
Method. Look at the shape. Is it round all over?
- Look at the shape. It is round all over, like a ball.round all over
- Check the faces. It has no flat faces.no flat faces
- Write the name. sphere
Check. A sphere can roll in any direction.
Watch out. A sphere is round all over.
Method. Look for the point and the base.
- Look for the point. It comes to a point at the top.a point
- Look at the bottom. It has a flat round base.round base
- Write the name. cone
Check. A cone has one point and one round base.
Watch out. A cone has one point. A cube does not.
Method. Look at the faces.
- Look at the faces. The faces are square.square faces
- Count the faces. It has six square faces.6
- Write the name. cube
Check. Six square faces are a cube.
Watch out. A cube has faces that are all the same size.
Watch out
Watch out. A cuboid can look like a cube. In a cuboid, some faces are longer than others.
Exam tip
Grown-up tip. Use boxes, balls and cones from around the house. Ask: “Which can roll?” and “Which has a point?”
Exercise 10C Solid shapes
Non-calculatorMethod. Look at the picture. Think about the faces and the points.
- Look at the shape. all faces are squares, and it has corners all the samecube
- Match the name. It has 6 square faces.cube
- Write the answer. cube
Check. Compare with the other shapes. Only a cube looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it looks like a box, with flat facescuboid
- Match the name. It has 6 faces, some rectangles.cuboid
- Write the answer. cuboid
Check. Compare with the other shapes. Only a cuboid looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Think about which shape is round like a ball.
- Look for the shape with no flat faces. A ball has no flat faces.sphere
- Check it can roll. A ball rolls in any direction.sphere can roll
- Write the answer. sphere
Check. A cone has a flat base, so it cannot roll in every way. ✓
Watch out. A sphere is round all over. It has no flat faces.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it has a point at the top and a round basecone
- Match the name. It has a flat round base and a point.cone
- Write the answer. cone
Check. Compare with the other shapes. Only a cone looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. all faces are squares, and it has corners all the samecube
- Match the name. It has 6 square faces.cube
- Write the answer. cube
Check. Compare with the other shapes. Only a cube looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Think about which shape is round like a ball.
- Look for the shape with no flat faces. A ball has no flat faces.sphere
- Check it can roll. A ball rolls in any direction.sphere can roll
- Write the answer. sphere
Check. A cone has a flat base, so it cannot roll in every way. ✓
Watch out. A sphere is round all over. It has no flat faces.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it is round like a ball, and it can rollsphere
- Match the name. It has no flat faces.sphere
- Write the answer. sphere
Check. Compare with the other shapes. Only a sphere looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it has a point at the top and a round basecone
- Match the name. It has a flat round base and a point.cone
- Write the answer. cone
Check. Compare with the other shapes. Only a cone looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Think about which shape is round like a ball.
- Look for the shape with no flat faces. A ball has no flat faces.sphere
- Check it can roll. A ball rolls in any direction.sphere can roll
- Write the answer. sphere
Check. A cone has a flat base, so it cannot roll in every way. ✓
Watch out. A sphere is round all over. It has no flat faces.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it looks like a box, with flat facescuboid
- Match the name. It has 6 faces, some rectangles.cuboid
- Write the answer. cuboid
Check. Compare with the other shapes. Only a cuboid looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it is round like a ball, and it can rollsphere
- Match the name. It has no flat faces.sphere
- Write the answer. sphere
Check. Compare with the other shapes. Only a sphere looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Think about which shape is round like a ball.
- Look for the shape with no flat faces. A ball has no flat faces.sphere
- Check it can roll. A ball rolls in any direction.sphere can roll
- Write the answer. sphere
Check. A cone has a flat base, so it cannot roll in every way. ✓
Watch out. A sphere is round all over. It has no flat faces.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. all faces are squares, and it has corners all the samecube
- Match the name. It has 6 square faces.cube
- Write the answer. cube
Check. Compare with the other shapes. Only a cube looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it looks like a box, with flat facescuboid
- Match the name. It has 6 faces, some rectangles.cuboid
- Write the answer. cuboid
Check. Compare with the other shapes. Only a cuboid looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Think about which shape is round like a ball.
- Look for the shape with no flat faces. A ball has no flat faces.sphere
- Check it can roll. A ball rolls in any direction.sphere can roll
- Write the answer. sphere
Check. A cone has a flat base, so it cannot roll in every way. ✓
Watch out. A sphere is round all over. It has no flat faces.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it has a point at the top and a round basecone
- Match the name. It has a flat round base and a point.cone
- Write the answer. cone
Check. Compare with the other shapes. Only a cone looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Sorting shapes
We can sort shapes into groups. Pick one thing to look at, like the number of corners.
The shape that does not match the others is the odd one out.
Key ideas
- Sort by one property, such as corners or sides.
- The odd one out is different from the others.
- Say why the odd one out is different.
Method. Count the corners of each shape.
- Count the corners. A and B are squares, with 4 corners each.A: 4, B: 4
- Check C. The circle has no corners.C: 0
- Write the letter. C is different.C
Check. Only the circle has no corners, so C is the odd one out.
Watch out. Choose the property that matches two shapes and not the third.
Method. Count the sides of each shape.
- Count the sides. A and B are triangles, with 3 sides.A: 3, B: 3
- Check C. The rectangle has 4 sides.C: 4
- Write the letter. C has a different number of sides.C
Check. Triangles have 3 sides. C has 4, so it is the odd one out.
Watch out. Count the sides of each shape before you decide.
Method. Count the corners of each shape.
- Count the corners. A square has 4 corners. A triangle has 3.4 and 3
- Find the group with 3 corners. The shape with 3 corners is a triangle.triangle
- Write the answer. triangle
Check. Three corners go in the triangle group.
Watch out. Count the corners to decide which group a shape goes in.
Watch out
Watch out. Sort by one property at a time. Do not change the rule halfway through.
Exam tip
Grown-up tip. Lay out shapes from the house or cut them from card. Ask your child to sort them into two piles, then say the rule.
Exercise 10D Sorting shapes
Non-calculatorMethod. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The rectangles have the same number of sides and corners.rectangle: 4 corners
- Find the different one. The other three are rectangles, and circle is different. It has no corners and no straight sides.circle is different
- Write the answer. A
Check. The letter A is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The triangles have the same number of sides and corners.triangle: 3 corners
- Find the different one. The other three are triangles, and circle is different. It has no corners and no straight sides.circle is different
- Write the answer. B
Check. The letter B is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The squares have the same number of sides and corners.square: 4 corners
- Find the different one. The other three are squares, and circle is different. It has no corners and no straight sides.circle is different
- Write the answer. B
Check. The letter B is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The triangles have the same number of sides and corners.triangle: 3 corners
- Find the different one. The other three are triangles, and circle is different. It has no corners and no straight sides.circle is different
- Write the answer. A
Check. The letter A is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The squares have the same number of sides and corners.square: 4 corners
- Find the different one. The others have 4 corners. It has 3 sides and 3 corners. The others have 4.triangle is different
- Write the answer. D
Check. The letter D is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The triangles have the same number of sides and corners.triangle: 3 corners
- Find the different one. The other three are triangles, and square is different. It is a square. The others are triangles, with 3 corners.square is different
- Write the answer. B
Check. The letter B is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The rectangles have the same number of sides and corners.rectangle: 4 corners
- Find the different one. The others have 4 corners. It has 3 sides and 3 corners. The others have 4.triangle is different
- Write the answer. D
Check. The letter D is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The triangles have the same number of sides and corners.triangle: 3 corners
- Find the different one. The other three are triangles, and rectangle is different. It is a rectangle. The others are triangles, with 3 corners.rectangle is different
- Write the answer. B
Check. The letter B is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The squares have the same number of sides and corners.square: 4 corners
- Find the different one. The other three are squares, and circle is different. It has no corners and no straight sides.circle is different
- Write the answer. A
Check. The letter A is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The triangles have the same number of sides and corners.triangle: 3 corners
- Find the different one. The other three are triangles, and square is different. It is a square. The others are triangles, with 3 corners.square is different
- Write the answer. C
Check. The letter C is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The rectangles have the same number of sides and corners.rectangle: 4 corners
- Find the different one. The others have 4 corners. It has 3 sides and 3 corners. The others have 4.triangle is different
- Write the answer. A
Check. The letter A is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The triangles have the same number of sides and corners.triangle: 3 corners
- Find the different one. The other three are triangles, and rectangle is different. It is a rectangle. The others are triangles, with 3 corners.rectangle is different
- Write the answer. A
Check. The letter A is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The squares have the same number of sides and corners.square: 4 corners
- Find the different one. The others have 4 corners. It has 3 sides and 3 corners. The others have 4.triangle is different
- Write the answer. C
Check. The letter C is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The triangles have the same number of sides and corners.triangle: 3 corners
- Find the different one. The other three are triangles, and rectangle is different. It is a rectangle. The others are triangles, with 3 corners.rectangle is different
- Write the answer. A
Check. The letter A is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The squares have the same number of sides and corners.square: 4 corners
- Find the different one. The other three are squares, and circle is different. It has no corners and no straight sides.circle is different
- Write the answer. A
Check. The letter A is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The triangles have the same number of sides and corners.triangle: 3 corners
- Find the different one. The other three are triangles, and circle is different. It has no corners and no straight sides.circle is different
- Write the answer. B
Check. The letter B is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Chapter summary
| Skill | Method |
|---|---|
| 2-D shapes | Circle, square, triangle, rectangle. Count the sides and corners |
| 3-D shapes | Cube (6 square faces), cuboid (box), sphere (round), cone (point and round base) |
| Sorting | Choose one property, sort, and find the odd one out |
| Next level | Level 2: counting in ones to 50 and 100, number lines and bonds to 20 |
Can you…?
- I can name a circle, square, triangle and rectangle
- I can count the sides and corners of a flat shape
- I can name a cube, cuboid, sphere and cone
- I can sort shapes and say which one does not belong
Key terms
- 2-D shape
- a flat shape, with length and width only
- 3-D shape
- a solid shape, with length, width and depth
- side
- a straight edge of a flat shape
- corner
- the point where two sides meet
- face
- a flat surface of a solid shape
- odd one out
- the shape that is different from the others
Exercise 10Z Check-up
Non-calculatorMethod. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.square
- Check the sides. It has 4 equal sides.4 equal sides
- Write the name. square
Check. A square has 4 corners and 4 equal sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.square
- Check the sides. It has 4 equal sides.4 equal sides
- Write the name. square
Check. A square has 4 corners and 4 equal sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.rectangle
- Check the sides. It has 2 long sides and 2 short sides.2 long sides and 2 short sides
- Write the name. rectangle
Check. A rectangle has 4 corners and 2 long sides and 2 short sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.circle
- Count the straight sides. A circle has no straight sides.0
- Write the answer. 0
Check. A circle has no corners and no straight sides.
Watch out. A curved line is not a side. Count only straight edges.
Method. Count the corners. A corner is where two straight sides meet.
- Find each corner. Mark each point where two straight sides meet.circle
- Count the corners. A circle has no corners.0
- Write the answer. 0
Check. Count the corners again, one at a time. ✓
Watch out. Count each corner once. The round shape has none.
Method. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.square
- Count the straight sides. A square has 4 equal sides.4
- Write the answer. 4
Check. The number of corners is the same as the number of straight sides for these shapes. ✓
Watch out. A curved line is not a side. Count only straight edges.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. all faces are squares, and it has corners all the samecube
- Match the name. It has 6 square faces.cube
- Write the answer. cube
Check. Compare with the other shapes. Only a cube looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it looks like a box, with flat facescuboid
- Match the name. It has 6 faces, some rectangles.cuboid
- Write the answer. cuboid
Check. Compare with the other shapes. Only a cuboid looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The squares have the same number of sides and corners.square: 4 corners
- Find the different one. The others have 4 corners. It has 3 sides and 3 corners. The others have 4.triangle is different
- Write the answer. A
Check. The letter A is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The triangles have the same number of sides and corners.triangle: 3 corners
- Find the different one. The other three are triangles, and square is different. It is a square. The others are triangles, with 3 corners.square is different
- Write the answer. B
Check. The letter B is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Total 28 marks. Allow about 28 minutes.
Exercise 10X Level 1 check
Non-calculatorMethod. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.square
- Check the sides. It has 4 equal sides.4 equal sides
- Write the name. square
Check. A square has 4 corners and 4 equal sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 3 corners.triangle
- Check the sides. It has 3 sides.3 sides
- Write the name. triangle
Check. A triangle has 3 corners and 3 sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 3 corners.triangle
- Check the sides. It has 3 sides.3 sides
- Write the name. triangle
Check. A triangle has 3 corners and 3 sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.rectangle
- Check the sides. It has 2 long sides and 2 short sides.2 long sides and 2 short sides
- Write the name. rectangle
Check. A rectangle has 4 corners and 2 long sides and 2 short sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.triangle
- Count the straight sides. A triangle has 3 sides.3
- Write the answer. 3
Check. The number of corners is the same as the number of straight sides for these shapes. ✓
Watch out. A curved line is not a side. Count only straight edges.
Method. Count the corners. A corner is where two straight sides meet.
- Find each corner. Mark each point where two straight sides meet.square
- Count the corners. A square has 4 corners.4
- Write the answer. 4
Check. Count the corners again, one at a time. ✓
Watch out. Count each corner once. The round shape has none.
Method. Count the straight edges. A curved edge is not a side.
- Trace the outline with your finger. Count each straight edge once.circle
- Count the straight sides. A circle has no straight sides.0
- Write the answer. 0
Check. A circle has no corners and no straight sides.
Watch out. A curved line is not a side. Count only straight edges.
Method. Count the corners. A corner is where two straight sides meet.
- Find each corner. Mark each point where two straight sides meet.square
- Count the corners. A square has 4 corners.4
- Write the answer. 4
Check. Count the corners again, one at a time. ✓
Watch out. Count each corner once. The round shape has none.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. all faces are squares, and it has corners all the samecube
- Match the name. It has 6 square faces.cube
- Write the answer. cube
Check. Compare with the other shapes. Only a cube looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it looks like a box, with flat facescuboid
- Match the name. It has 6 faces, some rectangles.cuboid
- Write the answer. cuboid
Check. Compare with the other shapes. Only a cuboid looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Think about which shape is round like a ball.
- Look for the shape with no flat faces. A ball has no flat faces.sphere
- Check it can roll. A ball rolls in any direction.sphere can roll
- Write the answer. sphere
Check. A cone has a flat base, so it cannot roll in every way. ✓
Watch out. A sphere is round all over. It has no flat faces.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it has a point at the top and a round basecone
- Match the name. It has a flat round base and a point.cone
- Write the answer. cone
Check. Compare with the other shapes. Only a cone looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The rectangles have the same number of sides and corners.rectangle: 4 corners
- Find the different one. The other three are rectangles, and circle is different. It has no corners and no straight sides.circle is different
- Write the answer. B
Check. The letter B is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The triangles have the same number of sides and corners.triangle: 3 corners
- Find the different one. The other three are triangles, and square is different. It is a square. The others are triangles, with 3 corners.square is different
- Write the answer. D
Check. The letter D is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The rectangles have the same number of sides and corners.rectangle: 4 corners
- Find the different one. The other three are rectangles, and circle is different. It has no corners and no straight sides.circle is different
- Write the answer. A
Check. The letter A is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Count the sides and corners of each shape. Find the one that is different.
- Count the sides and corners. The triangles have the same number of sides and corners.triangle: 3 corners
- Find the different one. The other three are triangles, and rectangle is different. It is a rectangle. The others are triangles, with 3 corners.rectangle is different
- Write the answer. C
Check. The letter C is the one that does not belong. ✓
Watch out. The odd one out has a different number of sides or corners, or no corners at all.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.rectangle
- Check the sides. It has 2 long sides and 2 short sides.2 long sides and 2 short sides
- Write the name. rectangle
Check. A rectangle has 4 corners and 2 long sides and 2 short sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the shape. Count its sides and corners, then match it to a name.
- Look at the outline. It has 4 corners.square
- Check the sides. It has 4 equal sides.4 equal sides
- Write the name. square
Check. A square has 4 corners and 4 equal sides. ✓
Watch out. Turned shapes are still the same shape. A square turned on its corner is still a square.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. all faces are squares, and it has corners all the samecube
- Match the name. It has 6 square faces.cube
- Write the answer. cube
Check. Compare with the other shapes. Only a cube looks like this. ✓
Watch out. Look for flat faces, round faces and points.
Method. Look at the picture. Think about the faces and the points.
- Look at the shape. it looks like a box, with flat facescuboid
- Match the name. It has 6 faces, some rectangles.cuboid
- Write the answer. cuboid
Check. Compare with the other shapes. Only a cuboid looks like this. ✓
Watch out. Look for flat faces, round faces and points.