You will learn
- Say which person or object is taller or shorter.
- Compare heights side by side.
- Use tallest and shortest for three objects.
- Explain a fair way to compare height.
Version 0.2 · expanded edition · expert review pending Standards alignment: pending verification. Written in the style of common primary school assessments. No exam result is promised.
Student lesson
- Taller means more height. Shorter means less height.
- Stand things side by side on the same flat ground.
- Tallest is the most tall of three or more. Shortest is the least tall.
- A fair comparison needs the same level ground.
Words to know
Large from bottom to top.
More tall than.
The most tall of three or more.
The least tall of three or more.
1. Discover: two trees
Look at two trees outside. One looks taller. How can we be sure? What if one tree is on a hill?
2. Understand: taller and shorter
To compare how tall things are, stand them on the same flat ground. The one that reaches higher is taller. The other is shorter.
With three things we say tallest (most tall) and shortest (least tall).
Tall and long mean the same idea of measuring end to end, but we use tall for up-and-down height.
Idea 1: Tall and short
A giraffe is taller than a cat. The cat is shorter than the giraffe. Height is how high something is from bottom to top.
Idea 2: Compare side by side
Stand two things side by side on the same flat ground. Look at their tops. The one that reaches higher is taller.
Why the same ground? If one is on a hill, it looks taller than it is.
Idea 3: Tallest and shortest
For three towers, the one that reaches highest is the tallest. The one that reaches least is the shortest.
3. Worked examples
Example 1 (I show you): Giraffe and cat
A giraffe and a cat stand side by side. Which is taller?
- Look at the tops.
- The giraffe reaches higher.
Answer: The giraffe is taller. The cat is shorter.
Example 2 (We do it together): Three towers
Tower A is taller than B. B is taller than C. Which is the tallest and which is the shortest?
- A is taller than B.
- B is taller than C.
Answer: A is the tallest and C is the shortest.
Example 3 (You try): Three friends
Ama is taller than Kofi. Kofi is taller than Aisha. Order them from tallest.
Show the steps and answer
- Ama is taller than Kofi.
- Kofi is taller than Aisha.
Answer: Ama, Kofi, Aisha
Did you know?
The giraffe is the tallest animal in the world. Some giraffes are more than 5 metres tall.
Why this matters
We compare heights to choose a ladder, find who fits through a doorway or see how a plant grows.
4. Explore: back to back
You need two or three friends or objects.
- Stand two friends back to back on flat ground.
- Which head is higher?
- Say: __ is taller than __.
- Line up three objects. Say the tallest and shortest.
Think about it: what did you notice?
The one whose head or top is higher is taller.
5. Practise
Say it in a sentence
Use these starters when you talk about the lesson. Say them out loud.
- ___ is taller than ___.
- ___ is shorter than ___.
- ___ is the tallest.
- ___ is the shortest.
Guided practice
Question 1. A tree is taller than a house. Which is shorter?
The house.
Question 2. Of three towers, which is the tallest?
The one that reaches highest.
Question 3. Why stand on the same ground?
So the comparison is fair.
Independent practice
Level 1: Start
- Name something taller than you.
- Name something shorter than you.
- Which is taller: a giraffe or a cat?
- Draw three towers: tall, taller, tallest.
- Explain how to compare two trees fairly.
Level 2: Grow
- A tree is taller than a bush. The bush is ___ than the tree.
- Of three towers, which is the shortest?
- Ana is taller than Ben. Who is shorter?
Level 3: Stretch
- Ama is taller than Kofi. Kofi is taller than Aisha. Order them from tallest.
- Two trees: one on a hill and one in a valley. Why is it hard to compare them?
- Draw three plants: short, taller and tallest.
Answers are in the answer key below. Try first, then check.
6. Apply: everyday mathematics
A mango tree is 5 steps tall and a guava tree is 3 steps tall. Which tree is shorter?
Show a sample answer
The guava tree.
Another one. You are choosing which of two boxes fits on a shelf. How can you tell which is taller?
Show a sample answer
Stand them side by side on the same flat surface. The one that reaches higher is taller.
7. Common mistakes
Fix: Put both on the same flat ground.
Fix: Put both on the same flat ground.
Fix: Tall is how high from bottom to top, not how wide.
8. Lesson summary and revision card
- I can say which person or object is taller or shorter.
- I can compare heights side by side.
- I can use tallest and shortest for three objects.
- I can explain a fair way to compare height.
9. Check and master
Answer all 14 questions. You will see feedback after each one.
Your result appears here after you answer every question.
10. Key takeaways
- Compare height on level ground.
- Taller, shorter, tallest, shortest.
- Compare fairly.
11. Next lesson
Next lesson: Heavier and lighter. Keep going with the next idea in this course.
Exam practice
These questions are written in the style of common school and international primary assessments. Try them on your own, without looking back. Then check your answers in the marking guide. The marks are shown in brackets.
- A tree is taller than a bush. Which is shorter? [1 mark]
- Ama is taller than Kofi. Kofi is taller than Aisha. Who is the tallest? Who is the shortest? [2 marks]
- How do you compare the heights of two children fairly? [2 marks]
- Draw three towers: short, taller and tallest. [2 marks]
- Two children stand side by side. The tops of their heads are level. What can you say? [1 mark]
Total: 8 marks.
Marking guide and model answers
- The bush [1]
- Ama [1]; Aisha [1]
- Stand them side by side [1]; on the same flat ground [1]
- Three towers drawn [1]; heights in the right order [1]
- They are the same height [1]
Score guide: 7 to 8 = secure. 5 to 6 = nearly there, revise the parts you missed. Under 5 = work through the lesson again with a grown-up.
Printable worksheet
- Tallest: a mouse, a dog or a horse?
- Shortest: a mouse, a dog or a horse?
- A is taller than B. Who is shorter?
- Why stand on level ground?
- Draw a tall tree and a short tree.
- A giraffe is taller than a cat. Which is shorter?
- Of three towers, which is the tallest?
- A is taller than B. B is taller than C. Who is the shortest?
- Name something taller than you.
- Do we stand on the same ground to be fair?
Homework
Compare the heights of three things at home (a cup, a bottle, a cupboard). Put them in order from shortest to tallest.
Answer key and marking scheme
| Question | Expected response | Marks |
|---|---|---|
| Tallest: a mouse, a dog or a horse? | horse | 2 |
| Shortest: a mouse, a dog or a horse? | mouse | 2 |
| A is taller than B. Who is shorter? | B | 2 |
| Why stand on level ground? | to make the comparison fair | 2 |
| Draw a tall tree and a short tree. | one tall, one short | 2 |
| Total | 10 |
Practice answers: Worksheet: 1 horse; 2 mouse; 3 B; 4 to make the comparison fair; 5 one tall, one short.
Quiz answers: 1 A, 2 B, 3 C, 4 A, 5 B, 6 A, 7 B, 8 C, 9 A, 10 B, 11 C, 12 A, Challenge 1 C, Challenge 2 C.
Extra worksheet answers (items 6 onward): 6 The cat; 7 The one that reaches highest; 8 C; 9 A tree or a house; 10 Yes.
Independent practice answers. Level 1: 1 for example a tree; 2 for example a chair; 3 a giraffe; 4 three towers: a short one, a taller one and the tallest; 5 stand them side by side on the same flat ground and compare their tops. Level 2: 1 shorter; 2 The one that reaches the least high; 3 Ben. Level 3: 1 Ama, Kofi, Aisha; 2 They are not on the same level ground.; 3 Three plants of increasing height.
Mastery and remediation
| Objective | Bronze (Developing) | Silver (Proficient) | Gold (Advanced) |
|---|---|---|---|
| O1 Say which person or object is taller or shorter | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O2 Compare heights side by side | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O3 Use tallest and shortest for three objects | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O4 Explain a fair way to compare height | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
Proposed Courseversity thresholds for this page: Bronze = at least 8 of 12 core questions correct; Silver = all 12; Gold = all 12 plus both challenge questions. A badge is never a full record of progress.
If a learner struggles
- Find the misconception: Comparing heights when objects stand on different levels. Put both on the same flat ground.
- Explain another way: use real objects first, then pictures.
- Show a simpler example: Compare two very different heights first.
- Guided practice: work through one example together and let the learner try the next one.
- Reassess: use the quiz again or the worksheet.
- Move on when the learner shows Silver-level evidence independently.
For parents and guardians
In this lesson your child compares heights with the words taller, shorter, tallest and shortest. You do not need to be good at mathematics to help.
- Compare the heights of family members or plants.
- Stand back to back and see who is taller.
- Ask: who is the tallest? Who is the shortest?
- Ask “how do you know?” after each answer, and listen.
- Praise effort, not only right answers. Mistakes are how we learn.
- Ten to fifteen minutes a day is better than one long session.
Teacher package
1–5. Objectives, prerequisites, materials, preparation, duration
Lesson objectives. Learners will: say which person or object is taller or shorter; compare heights side by side; use tallest and shortest for three objects; explain a fair way to compare height.
Prerequisite knowledge. Lesson 1: longer and shorter.
Materials. Counters (stones, seeds or bottle tops), paper, pencils, board or chalkboard. Low-resource options: use stones, seeds, sticks, bottle tops or drawings in the sand or on the board instead of printed materials.
Preparation. Gather the counters and draw the example pictures on the board before the lesson.
Suggested duration. 45–60 minutes. It can be split into two shorter sessions.
6–9. Teaching procedure, explanation notes, guided and independent activities
Introduction (5 min). Start with the Discover situation and let learners suggest ideas before you teach.
Explanation (10 min). Teach the Understand section with real objects first, then pictures, then symbols and words.
Guided activity (10 min). You need two or three friends or objects. Learners follow the Explore steps in pairs.
Independent activity (10 min). Learners complete the independent practice and the worksheet.
Assessment and reflection (5 min). Ask each learner to say one thing they learned and how they know it.
Key questions. Who is taller? How do you know? Why do we use the same ground?
Teacher explanation notes. Use the concrete, pictorial, abstract order: real objects first, then pictures, then symbols and words. Return to real objects whenever a learner needs support.
10–12. Differentiation, formative assessment, common misconceptions
Support. Use real objects and work with a partner; say each step aloud together. Extension. Ask learners to make up their own example and explain it to a partner.
Formative assessment. Listen to learner explanations, ask “how do you know?”, and check the independent work.
Misconceptions. Comparing heights when objects stand on different levels. Put both on the same flat ground.
13–15. Assessment questions, answer keys, marking scheme
Use the quiz and worksheet on this page. The 8-mark exam practice scheme, the 10-mark scheme and all answers are in the answer sections above. Re-check every answer and the marking scheme before publication.
16–19. Remediation, enrichment, homework, teacher reflection
Remediation. Compare two very different heights first. Enrichment. Invite learners to find or create three more examples at home or in the classroom and explain them. Homework. See above.
Teacher reflection. After teaching, record: which concepts learners understood; which misconceptions occurred; which activities worked; which learners need more practice; and what to improve next time.
Sources and standards
Alignment is pending verification and no external endorsement is claimed. Reference starting points named in the Courseversity standard: Common Core State Standards for Mathematics, Cambridge Primary and the IB Primary Years Programme. Specific standard codes will be added once checked against the official documents.
Research used to shape this lesson. Common Core K.MD.A.2 (comparing measurable attributes); Cambridge Primary Mathematics Stage 1. These sources informed the lesson; no official alignment is claimed.