Year 1 - Maths
Composition of decade numbers to 100: making groups of 10
Counting in tens - decade numbers
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This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.
Unit Summary
In this unit pupils will extend their counting to counting the decade numbers which will later be known as multiples of ten and making representations of them using a variety of different manipulatives.
Lesson Summary
You will learn to recognise and count groups of ten.
Key Notes
- Objects can be put into groups of 10 to make them easier to count.
- You can recognise a group of 10 because when you separate them, there will be 10 objects.
- If there is not 10 in each group, they are not groups of 10.
- Groups of 10 can be called tens.
Vocabulary To Learn
- Group: Objects that are gathered together into a set are said to be in a group.
- Separate: When a group of objects are taken or split apart they have been separated.
Common Mistakes To Avoid
- Any group of objects can be counted in tens.
3 Quick Questions (With Answers)
1. Solve this in steps: explain the method from this lesson and why each step matters.
Objects can be put into groups of 10 to make them easier to count. You can recognise a group of 10 because when you separate them, there will be 10 objects.
2. Use this key word in a maths sentence and explain it clearly. 'Group'
Objects that are gathered together into a set are said to be in a group. Use this word when showing your method, then check your final answer is reasonable.
3. Spot and fix this common maths mistake.
Mistake: Any group of objects can be counted in tens. Correction: Identify groups that do and do not have 10 objects, drawing attention to the fact that colour, orientation and size are not relevant.
More Lessons In This Unit
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