Learning objectives
- I can count and write quantities up to 20.
- I can find the previous and next number.
- I can compare two small groups and explain my thinking.
Greek Primary Grade 1 / Mathematics / Two-unit revision pilot
Numbers up to 20
Numbers up to 20: structured theory, worked examples, answered practice, and a mastery checklist for Greek Primary Grade 1.
CHAPTER PLAN
Learn, practise, and check your progress
Follow the steps in order or jump directly to the part you need.
—/5
completed
Estimated active study time
93 minutes
1. Understand
Objectives, key ideas, and structured theory.
Open →2. Follow the method
Worked examples that explain every step.
Open →3. Practise
Graded tasks with hints and answer guidance.
Open →4. Consolidate
Assignments from core work to challenge.
Open →5. Check
A timed, marked test with solution guidance.
Open →
Progress is stored only in this browser and does not require AI credits.
Key ideas and checks
- Count every object once.
- The last counting number tells how many there are.
- 20 is two tens. The numbers here stay between 0 and 20.
Unit
Core theory
The essential chapter ideas in a clear sequence before practice.
Count and match
Point to one object for each number you say. Match the group to its numeral. Rearranging objects without adding or removing any does not change the count.
Before, after and between
On a number line, one step right adds one and one step left subtracts one. 12 is between 11 and 13.
Compare and combine groups
Compare two groups by pairing their objects. The group with objects left over is larger. When combining groups, count all their objects together.
Understanding the concept
Touch one object for each number you say. The final number tells how many there are altogether. Moving the objects without adding or removing any does not change the quantity.
Method and conditions
Compare two groups by making pairs. The group with unpaired objects has more. On a number line, the greater number lies further right.
Checking and coverage boundaries
To add, keep the original group and combine it with the new one. To subtract, remove only what was given away. Recount or use the inverse operation to check.
Original pilot material — human educator review pending
Written specifically for YourFavTeacher with AI assistance, without copying past-paper prompts. Technical and numerical checks do not replace review by a human educator. It is not an official paper or endorsed by an examination body.
Mathematics
Worked examples
Follow the method step by step and check why every step is valid.
Count a group
Count: ● ● ● ● ● ● ●.
- 1Point to each dot once, saying 1, 2, 3, 4, 5, 6, 7.
- 2The last number is 7, so write 7 for the count.
7
Combine two groups
You have 8 cards and receive 3 more. How many now?
- 1Start at 8 and count on three steps: 9, 10, 11.
- 2Check with two groups of objects, one of 8 and one of 3.
8 + 3 = 11
Worked example 3
There are 8 balls in a basket. How many must you add to make 12?
- 1Find how many steps are missing to reach the target.
- 212 − 8 = 4
- 3Check: 8+4=12.
4
Numbers up to 20
Practice with answers
Eight graded tasks from core fluency to exam-style application. Work independently before opening a hint or answer.
Core fluency3 minutes
Count the dots: ● ● ●.
Hint
Point to each dot once.
Answer guide
3
Core fluency3 minutes
Which number comes immediately after 11?
Hint
Move one step along the number line.
Answer guide
12
Application3 minutes
Which number comes immediately before 10?
Hint
Move one step back.
Answer guide
9
Application3 minutes
Fill the gap: 7, __, 9.
Hint
The numbers increase by one.
Answer guide
8
Reasoning3 minutes
Which is greater: 9 or 6?
Hint
Find which number is further right on the number line.
Answer guide
9
Reasoning3 minutes
Order from smallest to greatest: 8, 3, 5.
Hint
Find the smallest number first.
Answer guide
3, 5, 8
Exam style3 minutes
You have 3 pencils and receive 2 more. How many now?
Hint
Use objects or count on.
Answer guide
3 + 2 = 5
Exam style3 minutes
You give away 2 of your 5 cards. How many remain?
Hint
Remove the cards you gave away.
Answer guide
5 − 2 = 3
Common mistakes
- Counting an object twice.
- Skipping a counting number.
- Thinking a more spread-out group has more objects.
- Counting the same object twice.
- Assuming a more spread-out group has more objects.
- Adding when the story describes giving objects away.
Mastery check
- I can count and write quantities up to 20.
- I can find the previous and next number.
- I can compare two small groups and explain my thinking.
Numbers up to 20
Chapter homework
Six distinct assignments from core fluency to challenge, each with an estimated time, hint, and answer guide.
Core4 minutes
Count the dots: ● ● ● ●.
Hint
Point to each dot once.
Answer guide
4
Core4 minutes
Which number comes immediately after 12?
Hint
Move one step along the number line.
Answer guide
13
Stretch4 minutes
Which number comes immediately before 11?
Hint
Move one step back.
Answer guide
10
Stretch4 minutes
Fill the gap: 8, __, 10.
Hint
The numbers increase by one.
Answer guide
9
Challenge4 minutes
Which is greater: 10 or 7?
Hint
Find which number is further right on the number line.
Answer guide
10
Challenge4 minutes
Order from smallest to greatest: 9, 4, 6.
Hint
Find the smallest number first.
Answer guide
4, 6, 9
30 minutes / 30 marks
Full chapter test
A timed, full-mark self-assessment with model-answer guidance.
Use a pencil and objects. An adult may read the instructions. Take a break if needed; the time is a guide. Check answers at the end.
1. Count the dots: ● ● ● ● ●.
2 marksAnswer guide
5
2. Which number comes immediately after 13?
3 marksAnswer guide
14
3. Which number comes immediately before 12?
3 marksAnswer guide
11
4. Fill the gap: 9, __, 11.
4 marksAnswer guide
10
5. Which is greater: 11 or 8?
4 marksAnswer guide
11
6. Order from smallest to greatest: 10, 5, 7.
4 marksAnswer guide
5, 7, 10
7. You have 5 pencils and receive 4 more. How many now?
5 marksAnswer guide
5 + 4 = 9
8. You give away 4 of your 9 cards. How many remain?
5 marksAnswer guide
9 − 4 = 5
Unit
Official sources and verification
Curriculum reference sources. Always confirm the teaching sequence with the school and tutor.
Mathematics
Start with theory and core examples, then move to worked exercises and short test-style practice.
What this chapter covers
The structure follows the official textbook layout and is used to organise study.
Quantity and sequence
Comparing numbers
Adding and taking away with objects
Where to focus
The areas that usually create mistakes or need extra revision.
I can count and write quantities up to 20.
I can find the previous and next number.
I can compare two small groups and explain my thinking.
Sources, daily material, and resources
Where to start: textbook, daily material, PDFs, videos, and worked examples.
Start from the official textbook or specification referenced on the subject page.
Use the notes and examples as support, not as a replacement for the official syllabus.
Check the current syllabus version before exam preparation.
Practice by subtopic
Targeted practice before full tests so coverage is clear.
Count the dots: ● ● ●.
Which number comes immediately after 11?
Which number comes immediately before 10?
Fill the gap: 7, __, 9.
Which is greater: 9 or 6?
Order from smallest to greatest: 8, 3, 5.
You have 3 pencils and receive 2 more. How many now?
You give away 2 of your 5 cards. How many remain?
Mocks and progress checks
How to measure progress in this chapter and when it enters a cumulative mock.
Start with untimed practice by subtopic.
Move to a short timed checkpoint only after completing the mastery checklist.
Record each error with the correct method and revisit it after 48 hours.
Next step
What to do after finishing the chapter and how it connects to the next unit.
Complete the practice without support.
Explain the core method aloud in under two minutes.
Continue to the next chapter or request targeted tutor support.
Note: for the official examinable syllabus of each school year, always confirm with the school, tutor, and current Ministry/IEP announcements.