Year 2 2-D and 3-D shapes: check-up and quiz

Key words. A flat shape is 2-D. A solid shape is 3-D, so it has depth.

Method. Look at the shape. Think about its sides or faces, then match them to a name.

1. Look at the shape. It is a flat (2-D) shape.
   It is 6 straight sides and 6 corners
2. Find the name that matches. Only one shape name has these features.
   hexagon matches
3. Write the name.
   hexagon

Check. The hexagon has the features we looked for. ✓

Watch out. Look at the whole shape before you name it. Do not guess from one part.

Method. Trace each straight side with your finger, and count it once.

1. Trace the edge with your finger. Go round the outside of the shape once.
   one trip round the shape
2. Count the straight sides. Count each straight side once.
   5 straight sides
3. Write the answer.
   5

Check. Count the corners too: there are 5. ✓

Watch out. A curved edge is not a side. Count only the straight parts.

Key words. A flat shape is 2-D. A solid shape is 3-D, so it has depth.

Method. Look at the shape. Think about its sides or faces, then match them to a name.

1. Look at the shape. It is a solid (3-D) shape.
   It is a flat triangle base and 3 triangle sides that meet at a point
2. Find the name that matches. Only one shape name has these features.
   pyramid matches
3. Write the name.
   pyramid

Check. The pyramid has the features we looked for. ✓

Watch out. Look at the whole shape before you name it. Do not guess from one part.

Method. Count the flat faces of the cube. Count the ones you cannot see, like the bottom.

1. Look at the shape. A face is a flat surface.
   a cube
2. Count the flat faces. There are 6 flat faces on a cube.
   6 flat faces
3. Write the answer.
   6

Check. Faces plus vertices equals edges plus 2: 6 + 8 = 12 + 2. ✓

Watch out. Turn the shape in your mind. Hidden faces, like the base, still count.

Method. Count the vertices (corners) of the cuboid. Count the ones you cannot see, like the bottom.

1. Look at the shape. A vertex is a sharp corner point.
   a cuboid
2. Count the vertices (corners). There are 8 vertices (corners) on a cuboid.
   8 vertices (corners)
3. Write the answer.
   8

Check. Faces plus vertices equals edges plus 2: 6 + 8 = 12 + 2. ✓

Watch out. Turn the shape in your mind. Hidden faces, like the base, still count.

Method. Imagine folding the shape in half, down the middle from top to bottom.

1. Imagine a vertical fold. The fold line goes straight up and down.
   a straight up-and-down fold
2. Check the two halves. Folded along a straight up-and-down line, the two halves do not match.
   Do the two halves match?
3. Write the answer.
   No

Check. The shape is turned, so its line of symmetry slopes or goes sideways. A vertical fold does not match.

Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.

Method. Look at one flat face of the cylinder. Then name its shape.

1. Look at one flat face. A cylinder has flat faces that are circles.
   one flat face of the cylinder
2. Check its sides. Count the straight sides, or check if the face is round.
   round, with no straight sides
3. Name the shape. This flat face is a circle.
   circle

Check. Every flat face of this cylinder is the same kind of shape. ✓

Watch out. A face is flat, so it is a 2-D shape. The solid itself is 3-D.

Method. Check the shape of each shape. Then pick the one that matches.

1. Look at each shape. Check the shape of each one.
   A: cone has a point and a round flat base; B: cylinder has 2 flat ends; C: sphere has no flat faces
2. Find the one that matches. Only the cone has a point at the top and a round flat base.
   cone matches
3. Write the answer.
   cone

Check. Check each of the other shapes too. Only cone matches. ✓

Watch out. Check every shape, not only the first one you see.

Method. Check the flat or solid of each shape. Then pick the one that matches.

1. Look at each shape. Check the flat or solid of each one.
   A: cube is solid; B: circle is flat; C: cuboid is solid
2. Find the one that matches. A circle has no depth, so it is flat. The cube and cuboid are solid.
   B matches
3. Write the answer.
   B

Check. Check each of the other shapes too. Only B matches. ✓

Watch out. Check every shape, not only the first one you see.

Method. A square turned on its corner is still a square.

1. Look at the diamond. It has 4 straight sides, all the same length.
   4 equal sides
2. Think about turning. Turning a shape round does not change it.
   same shape turned
3. Decide. Sam is not right.
   No

Check. A diamond is a square turned on its corner. ✓

Watch out. A shape is still the same shape when it is turned.

Key words. A flat shape is 2-D. A solid shape is 3-D, so it has depth.

Method. Look at the shape. Think about its sides or faces, then match them to a name.

1. Look at the shape. It is a flat (2-D) shape.
   It is 5 straight sides and 5 corners
2. Find the name that matches. Only one shape name has these features.
   pentagon matches
3. Write the name.
   pentagon

Check. The pentagon has the features we looked for. ✓

Watch out. Look at the whole shape before you name it. Do not guess from one part.

Key words. A flat shape is 2-D. A solid shape is 3-D, so it has depth.

Method. Look at the shape. Think about its sides or faces, then match them to a name.

1. Look at the shape. It is a solid (3-D) shape.
   It is 2 flat circle ends and a curved side
2. Find the name that matches. Only one shape name has these features.
   cylinder matches
3. Write the name.
   cylinder

Check. The cylinder has the features we looked for. ✓

Watch out. Look at the whole shape before you name it. Do not guess from one part.

Method. Find every sharp point on the outside of the shape. Count each one once.

1. Find each corner. A corner is a sharp point where two sides meet.
   mark each sharp point
2. Count the corners. Each corner is counted once.
   2 corners
3. Write the answer.
   2

Check. Count the straight sides as well: there are 1. ✓

Watch out. A corner is sharp. A curved part has no corners.

Method. Count the faces of the cube.

1. Count the faces. A cube has 6 faces.
   6 faces
2. Compare with Ali. Ali says 8, which is 2 more.
   8 is not 6
3. Decide. Ali is not right.
   No

Check. A cube has 6 faces and 8 vertices. Ali mixed up the vertices. ✓

Watch out. Faces and vertices are different. Check which one you are counting.

Method. Check the number of straight sides of each shape. Then pick the one that matches.

1. Look at each shape. Check the number of straight sides of each one.
   A: triangle has 3 sides; B: oval has 0 sides
2. Find the one that matches. An oval has no straight sides.
   oval matches
3. Write the answer.
   oval

Check. Check each of the other shapes too. Only oval matches. ✓

Watch out. Check every shape, not only the first one you see.

Method. Imagine folding the shape in half, down the middle from top to bottom.

1. Imagine a vertical fold. The fold line goes straight up and down.
   a straight up-and-down fold
2. Check the two halves. Folded along a straight up-and-down line, the two halves match exactly.
   Do the two halves match?
3. Write the answer.
   Yes

Check. Trace one half, then the other. They are the same shape. ✓

Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.

Method. Look at one flat face of the cuboid. Then name its shape.

1. Look at one flat face. A cuboid has flat faces that are rectangles.
   one flat face of the cuboid
2. Check its sides. Count the straight sides, or check if the face is round.
   4 straight sides, two long and two short
3. Name the shape. This flat face is a rectangle.
   rectangle

Check. Every flat face of this cuboid is the same kind of shape. ✓

Watch out. A face is flat, so it is a 2-D shape. The solid itself is 3-D.

Method. Look at each side of the diamond.

1. Look at the sides. All the sides of a diamond are the same length.
   all 4 equal
2. Count the equal sides. There are 4 sides, and they are all the same.
   4 equal sides
3. Write the answer.
   4

Check. A diamond has 4 straight sides, so all 4 are equal. ✓

Watch out. The number of equal sides is the number of sides here.

Method. Check the number of vertices of each shape. Then pick the one that matches.

1. Look at each shape. Check the number of vertices of each one.
   A: cube has 8 vertices; B: pyramid has 4 vertices
2. Find the one that matches. Only the cube has 8 vertices.
   cube matches
3. Write the answer.
   cube

Check. Check each of the other shapes too. Only cube matches. ✓

Watch out. Check every shape, not only the first one you see.

Method. Imagine folding the shape in half, down the middle from top to bottom.

1. Imagine a vertical fold. The fold line goes straight up and down.
   a straight up-and-down fold
2. Check the two halves. Folded along a straight up-and-down line, the two halves match exactly.
   Do the two halves match?
3. Write the answer.
   Yes

Check. Trace one half, then the other. They are the same shape. ✓

Watch out. A vertical line goes straight up and down. A sideways or slanting line does not count here.