The idea, step by step
The situation matters
A need is something required for a purpose or for living safely and well. A want is something a person would like but can do without in that situation.
Needs and wants are not always the same for everyone. A bus ticket may be needed to reach school. Another child may walk safely and not need that ticket. Explain the situation instead of judging the person.
Use a budget to choose
A budget is the amount of money available. List essential costs first, then compare other choices with the money left.
A reasonable answer includes both a calculation and a reason. Different choices can be sensible when they meet the stated needs and stay within the budget.
| Choice | Cost |
|---|---|
| Required bus ticket | 5 dollars |
| Fruit to go with a packed lunch | 2 dollars |
| Optional souvenir sticker | 3 dollars |
A common trap
An item is always a need or always a want for every person.
Instead: Use the stated purpose, available alternatives and budget to explain a decision.
See the thinking
Meet the stated need
For the outing above, a child must buy the bus ticket and has 7 dollars. Can they also buy the 3-dollar sticker?
- After the required ticket, dollars remain.
- The sticker costs 3 dollars, more than the 2 dollars left.
Explain a different situation
A student needs a pencil for class. A plain pencil costs 50 cents and a decorated pencil costs 2 dollars. The budget is 1 dollar. Suggest a plan.
- Both pencils can meet the writing need.
- Only the plain pencil fits a 1-dollar budget.
- cents remain.
Check your understanding
A required ticket costs 4 dollars. You have 6 dollars. An optional toy costs 3 dollars. Can you buy both?
Show answer
No.
dollars, which is 1 dollar above the budget.
Your turn
6 questions · Work at your own pace.
Read the questions online
- A child has lunch packed but needs a 2-dollar bus ticket to reach the outing. Which is the stated need: the ticket or an optional badge?
- You have 5 dollars. A required workbook costs 3 dollars. How much remains?
- Using the previous budget, can you also buy a 3-dollar sticker set? Explain.
- A required pencil costs 60 cents. You have 1 dollar. Choose either a 20-cent sticker or a 50-cent eraser as an extra. Give an affordable plan.
- One child needs shoes for sport. Another already has suitable shoes. Explain why buying shoes could be a different priority for them.
- You must spend 4 dollars on materials and have 8 dollars. Suggest a reasonable use for the remaining 4 dollars and explain it.
Read the worked solutions
- A child has lunch packed but needs a 2-dollar bus ticket to reach the outing. Which is the stated need: the ticket or an optional badge?
The ticket is required for travel in this situation; the badge is optional.
The bus ticket. - You have 5 dollars. A required workbook costs 3 dollars. How much remains?
.
2 dollars. - Using the previous budget, can you also buy a 3-dollar sticker set? Explain.
dollars, above the 5-dollar budget.
No. Only 2 dollars remain, so it is 1 dollar short. - A required pencil costs 60 cents. You have 1 dollar. Choose either a 20-cent sticker or a 50-cent eraser as an extra. Give an affordable plan.
cents. The pencil and eraser would cost 110 cents, too much.
The pencil and sticker cost 80 cents and leave 20 cents. - One child needs shoes for sport. Another already has suitable shoes. Explain why buying shoes could be a different priority for them.
Use the different situations; no single purchase priority fits everyone.
The first child may need shoes to take part safely. The second may not need another pair now. - You must spend 4 dollars on materials and have 8 dollars. Suggest a reasonable use for the remaining 4 dollars and explain it.
dollars remain. Another clearly explained affordable choice is acceptable.
For example, save the remaining 4 dollars for the next materials purchase.
Curriculum reference & lesson scope
Australian Curriculum v9 and SA Curriculum Mathematics
Dollars/cents; equivalent amounts; modelling purchases; needs/wants; class enterprise and others' wellbeing.
Official curriculum source ↗