COUNTING & NUMBER SENSE · TEXTBOOK LESSON
Number sense is the ability to recognise quantities, connect quantities to numerals, compare amounts and understand how numbers are ordered. Strong number sense makes later addition, subtraction and place value much easier.
Learning objectives
By the end of this lesson, you should be able to:
- Match a spoken number, a written numeral and a quantity.
- Count objects accurately using one-to-one correspondence.
- Compare two quantities using more, fewer, greater than, less than or equal to.
- Place numbers in order and explain which number comes before or after another.
1. Key vocabulary and definition
Definition
A number tells us how many objects there are or where something is in an order. A numeral is the written symbol used to represent that number, such as 7.
numbernumeralquantitycountmorefewerorder
2. Essential facts and rules
These are the facts you should know before attempting the worked example.
Key mathematical facts
- Touch or move each object once when counting so that no object is counted twice.
- The last number said when counting a group tells the total number of objects.
- Numbers farther to the right on a number line are greater.
3. Standard method
A reliable method helps prevent errors and makes your reasoning easy to follow.
1
Say the counting sequence in order.
2
Point to or move one object for each number word.
3
Match the final count to the correct numeral.
4
For comparison, line up objects or use a number line.
5
Describe the result using correct comparison language.
4. Worked example
Worked example
There are 8 counters in one group and 5 counters in another. Which group has more?
1
Count the first group: 1, 2, 3, 4, 5, 6, 7, 8.
2
Count the second group: 1, 2, 3, 4, 5.
3
Compare 8 and 5. Since 8 comes after 5 when counting, 8 is greater than 5.
4
The group with 8 counters has 3 more counters.
5. Common mistakes
Watch out for these
- Starting calculations before deciding what the question is asking.
- Skipping important steps or changing notation midway through a solution.
- Accepting an answer without checking whether its size, sign or unit is sensible.
6. Video lesson
This topic is ready for a matching video lesson. The written textbook lesson is fully available now; additional videos can be added to the same lesson template.
7. Practice exercise
Complete these without looking at the answers first.
- Count 12 objects and write the matching numeral.
- Which is greater: 9 or 6? Explain how you know.
- Put 4, 10, 2 and 7 in ascending order.
- Draw a group of objects to represent the number 8.
- What number comes immediately before 15 and immediately after 15?
Show answers
- 12
- 9 is greater than 6
- 2, 4, 7, 10
- Any group containing exactly 8 objects
- 14 and 16
8. Chapter summary
- Understand the underlying idea before memorising a procedure.
- Use precise mathematical notation and show a logical method.
- Always check the final result.