You will learn
- Add two numbers with a total up to 20.
- Use make-ten to add.
- Know doubles up to 10 + 10.
- Explain a strategy for adding.
Version 0.2 · expanded edition · built from cited public sources Content is based on the official frameworks and sources listed under Sources and standards. No official endorsement is claimed. Written in the style of common primary school assessments. No exam result is promised.
Student lesson
- Add two numbers with a total up to 20.
- Make ten first: 9 + 5 is 9 + 1 + 4.
- Doubles: a number added to itself, like 6 + 6 = 12.
- Say how you worked it out.
Words to know
The total in an addition.
Add the same number twice, like 4 + 4.
Fill up to 10 first, then add the rest.
A plan for solving a problem.
1. Discover: bigger sums
You have 8 stickers and get 5 more. Counting all 13 is slow. Is there a quicker way to add 8 + 5?
2. Understand: adding within 20
Make ten: 8 + 5. Take 2 from the 5 to make 8 into 10. Then 10 + 3 = 13.
Doubles: adding the same number twice. 4 + 4 = 8, 6 + 6 = 12, 9 + 9 = 18. Near doubles: 6 + 7 is 6 + 6 + 1 = 13.
Use whichever strategy is easy, and check with objects or a picture.
Idea 1: Make ten
To add 8 + 5: 8 needs 2 more to make 10. Split 5 into 2 and 3. Then 8 + 2 = 10 and 10 + 3 = 13.
Why? Adding to ten is easy, and then you only add what is left.
Idea 2: Doubles
A double is a number added to itself. 1+1=2, 2+2=4, 3+3=6, 4+4=8, 5+5=10, 6+6=12, 7+7=14, 8+8=16, 9+9=18, 10+10=20.
Idea 3: Near doubles
For 6 + 7, know that double 6 is 12. 7 is one more than 6, so the answer is 12 + 1 = 13.
3. Worked examples
Example 1 (I show you): 9 + 4
Work out 9 + 4 by making ten.
- 9 needs 1 more to make 10.
- Split 4 into 1 and 3.
- 9 + 1 = 10.
- 10 + 3 = 13.
Answer: 9 + 4 = 13
Example 2 (We do it together): 7 + 7
Work out 7 + 7.
- This is a double.
- Start at 7 and count on 7, or use the doubles you know.
Answer: 7 + 7 = 14
Example 3 (You try): 6 + 7
Work out 6 + 7 using a double.
Show the steps and answer
- Double 6 is 12.
- 7 is one more than 6.
- 12 + 1 = 13.
Answer: 6 + 7 = 13
Did you know?
Spiders have 8 legs. Two spiders have 8 + 8 = 16 legs.
Why this matters
Adding to 20 is used in money, measuring and later mathematics. A good method is quicker and safer than counting one by one.
4. Explore: make ten
You need 20 counters and a ten frame.
- Put 9 counters in the ten frame. Add 4 more counters.
- Move 1 counter to fill the frame. Now you have 10 and 3 more.
- Say: 9 + 4 = 13.
- Try 7 + 5 and 8 + 6.
Think about it: what did you notice?
9 + 4 = 10 + 3 = 13. 7 + 5 = 12. 8 + 6 = 14.
5. Practise
Say it in a sentence
Use these starters when you talk about the lesson. Say them out loud.
- I made ten by ___.
- The double of ___ is ___.
- ___ + ___ = ___ because ___.
- My method was ___.
Guided practice
Question 1. 6 + 6 = ?
12.
Question 2. 9 + 3 = ?
9 + 1 = 10, then 2 more: 12.
Question 3. 8 + 4 = ?
8 + 2 = 10, then 2 more: 12.
Independent practice
Level 1: Start
- 7 + 7 = __
- 8 + 3 = __
- 9 + 5 = __
- 6 + 8 = __
- Explain how you add 8 + 7.
Level 2: Grow
- 9 + 6 = __
- 8 + 8 = __
- 7 + 5 = __
Level 3: Stretch
- Use make ten for 8 + 6. Show the steps.
- A spider has 8 legs. How many legs do two spiders have?
- Use the double 7 + 7 to work out 7 + 8.
Answers are in the answer key below. Try first, then check.
6. Apply: everyday mathematics
There are 9 red cars and 6 blue cars. How many cars?
Show a sample answer
9 + 6 = 15 cars.
Another one. You have 9 red beads and 7 blue beads. How many beads? Use make ten.
Show a sample answer
9 + 1 = 10, then 6 more: 16 beads.
7. Common mistakes
Fix: Use make-ten or doubles to be quick and accurate.
Fix: After 9 + 1 = 10, add what is left of the second number: 10 + 3.
Fix: Double 6 is 12. Check by counting on 6 from 6.
8. Lesson summary and revision card
- I can add two numbers with a total up to 20.
- I can use make ten to add.
- I can use doubles up to 10 + 10.
- I can explain how I added.
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
- Make ten first, then add the rest.
- Doubles help you add quickly.
- Check with objects or pictures.
11. Next lesson
Next lesson: Counting-on strategies. 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.
- Work out 8 + 7. Show your method. [2 marks]
- What is double 6? [1 mark]
- A bag has 9 oranges and another bag has 5 oranges. How many oranges altogether? [2 marks]
- 7 + 7 = 14. Use this to work out 7 + 8. [2 marks]
- Zoe says 6 + 8 = 13. Is she right? Explain. [2 marks]
Total: 9 marks.
Marking guide and model answers
- 15 [1]; a method such as 8 + 2 = 10, then 10 + 5 [1]
- 12 [1]
- 9 + 5 [1] = 14 [1]
- 7 + 8 is one more than 7 + 7 [1]; 15 [1]
- No [1]. 6 + 8 = 14 because 6 + 4 = 10 and 4 more is 14 [1].
Score guide: 8 to 9 = secure. 6 to 7 = nearly there, revise the parts you missed. Under 6 = work through the lesson again with a grown-up.
Printable worksheet
- 8 + 5 = __
- 6 + 6 = __
- 9 + 7 = __
- 10 + 6 = __
- 7 + 8 = __
- 9 + 3 = __
- 6 + 6 = __
- 8 + 9 = __
- 10 + 7 = __
- What is double 10?
Homework
Play a game with a family member. Pick two numbers from 5 to 10, add them using make-ten, and say the total.
Answer key and marking scheme
| Question | Expected response | Marks |
|---|---|---|
| 8 + 5 = __ | 13 | 2 |
| 6 + 6 = __ | 12 | 2 |
| 9 + 7 = __ | 16 | 2 |
| 10 + 6 = __ | 16 | 2 |
| 7 + 8 = __ | 15 | 2 |
| Total | 10 |
Practice answers: Worksheet: 1 13; 2 12; 3 16; 4 16; 5 15.
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 12; 7 12; 8 17; 9 17; 10 20.
Independent practice answers. Level 1: 1 14; 2 11; 3 14; 4 14; 5 8 + 2 = 10, then 10 + 5 = 15. So 8 + 7 = 15. Level 2: 1 15; 2 16; 3 12. Level 3: 1 8 + 2 = 10, then 10 + 4 = 14; 2 16; 3 14 + 1 = 15.
Mastery and remediation
| Objective | Bronze (Developing) | Silver (Proficient) | Gold (Advanced) |
|---|---|---|---|
| O1 Add two numbers with a total up to 20 | 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 Use make-ten to add | 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 Know doubles up to 10 + 10 | 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 strategy for adding | 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 |
Courseversity badge thresholds (overall quiz score): Gold = 90–100%; Silver = 80–89.9%; Bronze = 70–79.9%. A badge is never a full record of progress.
If a learner struggles
- Find the misconception: Counting from 1 each time and losing track. Use make-ten or doubles to be quick and accurate.
- Explain another way: use real objects first, then pictures.
- Show a simpler example: Practise number bonds to 10 with a ten frame, then add 1, 2 or 3 more.
- 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 adds numbers with totals up to 20 using make ten and doubles. You do not need to be good at mathematics to help.
- Practise doubles: 3 + 3, 4 + 4 and so on up to 10 + 10.
- Use fingers or counters to make ten first.
- Ask: how did you work it out?
- 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: add two numbers with a total up to 20; use make-ten to add; know doubles up to 10 + 10; explain a strategy for adding.
Prerequisite knowledge. Lesson 5: number bonds to 10.
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 20 counters and a ten frame. 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. How do you make ten? What is double 7? Can you use a double to help with 7 + 8?
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. Counting from 1 each time and losing track. Use make-ten or doubles to be quick and accurate.
13–15. Assessment questions, answer keys, marking scheme
Use the quiz and worksheet on this page. The 9-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. Practise number bonds to 10 with a ten frame, then add 1, 2 or 3 more. 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
This lesson is based on the sources below, and no official 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. Where a standard code is named, it points to the official framework.
Official standards for this topic area. Common Core State Standards for Mathematics (official site): Grade 1 » Operations & Algebraic Thinking; Grade 1 » Number & Operations in Base Ten. These pages list the standards that cover this topic area; read them alongside the lesson.
Research used to shape this lesson. Common Core 1.OA.C.6 (make a ten and doubles); Cambridge Primary Mathematics Stage 1. These sources informed the lesson.