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P1 Maths | 3D Shapes Lesson Guide for Tutors | Sphere, Cylinder, Cube, Cuboid
Pupils call a ball a circle because they only ever see solids as printed pictures. This lesson puts the solids in their hands so that flat and curved become something they can feel and test.
Objectives — Pupils can: 1) name a sphere, a cylinder, a cube and a cuboid after feeling them; 2) separate a sphere from a cylinder by testing how it rolls; 3) separate solids by whether they stack; 4) state that a cube has 6 faces, 12 edges and 8 vertices, and a cylinder has 2 flat faces.
01 Prerequisites (3-minute check)
If any of these fails, fix it before the lesson starts.
| Skill | Quick check | Pass mark |
|---|---|---|
| Naming 2D shapes | what shape is this (circle, square) | telling a face from the whole solid |
| Comparing size and length | which is bigger, which is longer | comparing solids of the same kind |
02 Lesson flow (35 minutes)
| Time | Stage | Tutor does | Student does |
|---|---|---|---|
| 0-5 min | Feel the shape | what does it feel like | smooth, corners, flat parts |
| 5-13 min | Rolling test | push it on the desk | sphere rolls any way, cylinder rolls one way |
| 13-21 min | Stacking test | can it be stacked | cube, cuboid and cylinder stack, sphere does not |
| 21-30 min | Count faces and edges | how many faces on a cube | 6 faces, 12 edges, 8 vertices |
| 30-35 min | Exit check | three questions | all correct to pass |
03 Teaching script (read it out)
Scene 1: Act 1: Hands before eyes
Put a sphere, a cylinder tin, a cube brick and a cuboid box into a bag. The pupil reaches in, picks one and describes the feel first, then names it. Pupils normally learn solids from printed pictures, and a picture flattens a sphere into a circle. Feeling a flat part and feeling no flat part gives them a test they can use later on any picture. Each guess is checked by pulling the solid out, and a wrong guess means feeling it again.
Tutor line: do you feel a flat part, or is the whole thing round? With a flat part it stops; all round and it rolls away.
Scene 2: Act 2: The rolling test separates sphere from cylinder
Put the sphere and the cylinder on a desk with a slight tilt and give each a gentle push. The sphere rolls in any direction because it has one continuous curved surface. The cylinder only rolls forwards and backwards, and refuses to roll sideways, because it stands on two flat circular ends. Let the pupil push and describe it, not you. Then ask how many flat faces a cylinder has; the answer is two, the top and the bottom, plus one curved surface.
Tutor line: push it and you know. The sphere rolls every way, the cylinder rolls one way because it has two flat ends.
Scene 3: Act 3: The stacking test and counting the structure
Hand over 4 cube bricks and ask for a tower. It stands steady because every face is flat and meets another flat face. Balance a sphere on top and it rolls off. Use one sentence to close it: only flat faces stack. Then count the cube: 6 faces (top, bottom, four sides), 12 edges where two faces meet, and 8 vertices where three edges meet. Ask the pupil to press a finger on one vertex and count the edges coming out of it; the answer is 3, which is how 8 vertices get counted without losing track.
Tutor line: flat faces stack. A cube has 6 faces, 12 edges and 8 vertices, and you can check them with one finger at a corner.
04 Question types and worked steps
| Type | Example | Steps | Answer |
|---|---|---|---|
| Naming | feel in the bag, describe, name it, then check | never accept a name from a picture alone | |
| Classifying by rolling | push on the desk, watch the direction, explain why | the reason must mention flat faces | |
| Testing stacking | try stacking two solids, note success or roll away, count flat faces | a sphere has zero flat faces | |
| Counting faces and edges | count faces, then press a vertex and count edges out of it, check the total | never count the same edge twice |
Sanity check (teach this): A sphere has no flat face, no edge and no vertex, only one curved surface; a cylinder has 2 flat faces plus 1 curved surface and must never be described as one face; both cube and cuboid have 6 faces, 12 edges and 8 vertices; stacking depends on flat faces, not on size.
05 Independent practice (3 questions)
| Question | Answer | What to watch |
|---|---|---|
| How many flat faces does a sphere have? | 0, only one curved surface | nothing flat to stand on, so it rolls |
| How many flat faces does a cylinder have? | 2, the top and the bottom | two circular ends |
| A desk has 3 boxes, 2 balls and 1 tin. How many objects in total? | 6 | 3 plus 2 plus 1 is 6 |
| How many layers can you make with 4 cube bricks? | 4 layers | every face is flat and meets another |
| Why can a sphere not be stacked? | it has no flat face, so it rolls off | the number of flat faces is zero |
06 Common mistakes and what to say
| Mistake | Student writes | Say this |
|---|---|---|
| Calling a sphere a circle | any round thing is called a circle | a circle is drawn on paper, a sphere rolls away. Does it have a flat part? |
| Saying a cylinder has one face | one face because it looks like one ring | the top and the bottom are two flat faces, plus the curved one, so three faces. |
| Counting an edge twice | the shape ends up with 14 edges | one edge counts once. Run your finger along it and do not go back. |
| Assuming the biggest solid stacks best | putting a big sphere at the bottom | stacking depends on flat faces, not size. A big sphere still rolls. |
07 Homework (paper, section and question numbers)
- Practice set for this chapter (questions 1 to 5 above) — questions 1 to 3 on flat faces and totals; questions 4 to 5 on stacking and reasons
- Primary Maths chapter index (related chapters) — question 6: find 3 cylinders and 2 spheres at home, write their names and test rolling
08 Exit check (last 5 minutes)
| Question | Answer | Decision |
|---|---|---|
| How many faces does a cube have? | 6 | wrong: recount with a finger on each face |
| Can a sphere be stacked, and why? | no, it has no flat face | wrong: redo the rolling and stacking test |
| Which way does a cylinder roll? | one way only, forwards and backwards | wrong: push again and point to the two flat ends |
09 Tutor FAQ
Do P1 pupils need the words vertex and edge?
They should recognise them, but no written definition is needed. Pointing and counting is the target; corner and side are acceptable first and are then replaced.
A pupil says a cylinder has three faces but cannot count them. Does that count as passing?
No. They must point to the two circular ends and then the curved surface, one at a time.
Should I teach with solids or with pictures?
Always with real solids. Pictures only teach the outline; only holding a solid shows how flat faces and rolling work.
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A TutorZone lesson-prep guide. Written by the TutorZone team; questions and lesson flow are original and are not taken from any school or publisher material.