Smart Spending

Overview

Students explore the value of New Zealand coins and notes, compare prices, and make spending decisions within a budget. They apply addition, subtraction and estimation in familiar shopping situations while explaining that the value of money depends on the amount, not the number of coins or notes.

Learning intentions

• WALT identify and compare the value of New Zealand coins and notes.
• WALT add prices and calculate how much money is left.
• WALT make sensible shopping choices within a budget.
• WALT explain our mathematical thinking using money representations.

Success criteria

• I can name coins and notes and state their values.
• I can compare two amounts using greater than, less than or equal to.
• I can calculate the total cost and the money remaining.
• I can explain why my shopping choices fit the budget.

Curriculum links

• Mathematics and Statistics — Number and Algebra: using addition and subtraction with whole numbers in money contexts.
• Mathematics and Statistics — mathematical modelling: representing and solving a familiar shopping problem.
• Mathematics and Statistics — communicating mathematical thinking and justifying decisions.
• Mathsteasers: challenging advanced learners through higher-order thinking and relevant problem-solving.

Lesson structure (40 minutes)

1. 0–5 min · Hook and prior knowledge. Teacher displays the opening of the money mystery slide deck and asks, “Which is worth more: five 20-cent coins or one $1 coin? How do you know?” Students think individually, discuss with a partner, and share different ways to prove their answer.

2. 5–12 min · Identify and compare. Teacher uses the coin and note images in the money mystery slide deck to review values, the dollar sign and decimal notation, modelling comparisons such as $2.00 and $1.95. Students read amounts aloud, order examples from least to greatest, and explain that different collections can have the same value.

3. 12–17 min · Model a budget. Teacher introduces a $10 school-canteen budget through the money mystery slide deck. Model choosing two or three items, adding prices efficiently, and finding the amount left by counting on or subtracting. Emphasise estimating first and checking that the total does not exceed $10. Students estimate the total for a worked example before checking the calculation.

4. 17–30 min · Partner shopping challenge. Teacher distributes the budget shopping challenge worksheet to pairs and explains that each pair must plan a purchase from the pictured price list without spending more than the stated budget. Students select items, record an addition equation, calculate the remaining money, and complete a second challenge comparing two possible shopping plans. Partners must agree and be ready to justify their decisions.

5. 30–35 min · Reasoning share. Teacher displays the discussion prompts in the money mystery slide deck and invites two or three pairs to present different solutions. Students compare strategies, check one another’s totals, and discuss whether the cheapest choice is always the best choice. Address errors by asking, “What could we do to check this?”

6. 35–40 min · Exit check and reflection. Teacher gives each student the final questions on the budget shopping challenge worksheet: “You have $8. You buy a $2.75 book and a $1.50 snack. How much is left?” and “Give one different way to make $1.00.” Students show their working and complete the sentence, “I know my budget works because…”. Collect responses for next-step planning.

Resources

• the money mystery slide deck
• the budget shopping challenge worksheet
• New Zealand coins and notes, real or classroom replicas
• Whiteboard and markers
• Calculators for checking only, if available
• Pencils and highlighters
• Pair work tables or desks

Assessment

• Listen during the hook and comparison activity for accurate coin and note values, use of mathematical language, and recognition of equivalent amounts.
• Check pair worksheets for correct totals, sensible estimation, accurate subtraction or counting-on, and a written explanation.
• Use the exit responses to identify students needing further support with decimal notation, addition, subtraction or understanding equivalent amounts.

Differentiation

• Support learners with real or replica money, a visible value chart, a number line, and sentence starters such as “I chose ___ because…” and “The total is ___, so I have ___ left.”
• Pair students strategically and allow learners to build amounts with coins before recording dollars and cents. Read all worksheet instructions aloud and provide enlarged, uncluttered copies for students who need them.
• For EAL learners, pre-teach and display: value, price, total, budget, cost, change and left over. Use gestures, pictures and repeated oral rehearsal before independent recording.
• Challenge confident mathematicians to find three different shopping plans with the same total, or to spend as close as possible to the budget without going over and prove that their plan is optimal.