The idea, step by step
Two kinds of answer
Data are answers or observations that we collect. A categorical answer names a group, such as a favourite fruit or a way of travelling. A count answer tells how many, such as the number of books in a bag.
A count is a whole number: 0, 1, 2 and so on. We do not count three and a half children. A quantity such as height is measured rather than counted.
Ask a clear question
Ask one thing at a time. Say which answer to give. “Which one fruit would you choose?” is clearer than “What fruit do you like?” when you want one vote per child.
Write group names for categorical answers and numbers for counts. A number on a bus can be a label, not a count of passengers.
| Fruit | Children |
|---|---|
| Apple | 6 |
| Banana | 4 |
| Orange | 2 |
A common trap
Every answer containing a number must be count data.
Instead: Ask what the number means. A classroom number is a label; the number of children inside is a count.
See the thinking
A named group
Mia asks, “Which fruit would you choose: apple, banana or orange?” What kind of data will she collect?
- The answers name fruits.
- Apple, banana and orange are categories, not counts.
Counting objects
Jai records 3 books, 0 books and 5 books in three bags. What kind of data is this?
- Each answer tells how many books are present.
- Zero is a valid count: that bag has no books.
Check your understanding
Is “number of pencils in a pencil case” categorical or count data?
Show answer
Count data.
The answer tells how many pencils there are.
Your turn
6 questions · Work at your own pace.
Read the questions online
- Is favourite sandwich filling categorical data or count data?
- Is the number of people in a family categorical data or count data?
- Write one possible answer to “How many pets live in your home?”
- Write one possible answer to “How do you usually travel to school?”
- Can 0 answer “How many books did you borrow?” Explain.
- A bus is labelled 12. Does 12 tell how many children are inside? Explain.
Read the worked solutions
- Is favourite sandwich filling categorical data or count data?
The answer names a filling, such as cheese.
Categorical data. - Is the number of people in a family categorical data or count data?
The answer counts people.
Count data. - Write one possible answer to “How many pets live in your home?”
An answer must be a whole-number count of pets.
For example, 2. Zero or another whole-number count is also possible. - Write one possible answer to “How do you usually travel to school?”
The answer names a way of travelling.
For example, walking. Car, bus or another clearly named way is also possible. - Can 0 answer “How many books did you borrow?” Explain.
Zero records an actual count rather than a missing answer.
Yes. It means no books were borrowed. - A bus is labelled 12. Does 12 tell how many children are inside? Explain.
A label does not count the passengers.
No. It is a route number or another bus identifier, not a passenger count.
Curriculum reference & lesson scope
Australian Curriculum v9 / South Australian Curriculum
Categorical/count data; recording; displays; comparisons; guided question-to-conclusion investigation.
Official curriculum source ↗