Intermediate
60 mins
Teacher/Student led
+85 XP
Teacher-led from the board — pupils need no device

Building the Project Budget (2): Categories, Totals and Accuracy

Learn to organise your project costs by grouping them into categories like materials and consumables. Calculate subtotals for each group, add a contingency of ten percent for unexpected expenses, and present all totals and percentages with the correct accuracy.

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    Budget builder
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    1 - Getting Started ~5 mins

    A class last year budgeted €300 to paint a set for the school play. They listed every tin and every brush. They forgot one line: contingency. Midway through the job the timber split and they needed an extra €28 of board. The budget was already full. The show still went on — but two students paid for the board out of their own pockets.

    Today you take the line items you already costed and turn them into a proper budget: categories, subtotals, a contingency line, and a grand total written to the right degree of accuracy. That finished sheet is Project Budget v2, and it goes straight into your MA1 portfolio.

    2 - What You'll Learn ~8 mins

    A list of prices is not yet a budget. A budget groups every line into a category, totals each category, adds a contingency for the unexpected, and writes every figure to the accuracy the job needs.

    ConceptWhy it mattersExample
    Budget category — a labelled group of related line items (materials, consumables, delivery, contingency)Lets you see at a glance where the money is going, and cut one group without touching the othersMaterials (paint, primer, timber) kept separate from Consumables (rollers, tape, sandpaper)
    Contingency — spare money, typically 10% of the materials total, for costs you have not met yetOne split board or a second tin of paint no longer blows the whole planMaterials €241 → contingency 10% = €24.10
    Degree of accuracy — how precisely you write each figure (nearest cent, nearest euro, one decimal place)A total written two different ways looks like two different answers; pick a rule and stick to itMoney to the nearest cent (€24.10); contingency rate as 10% or 10.0%
    Subtotal and grand total — sum inside one category, then sum of every category including contingencyThe grand total is the number you hold against the project ceilingMaterials €241 + Consumables €28 + Delivery €35 + Contingency €24.10 = €328.10

    Below is a worked school-set paint budget already grouped. Read the three sections and the balance against the €450 ceiling.

    3 - Try It Yourself ~17 mins

    Open the budget builder in explore mode. Load the starter example if it is not already there, then rebuild it so every line sits in the right category.

    1. Keep the project ceiling in Money coming in at €450.
    2. Put the materials lines under Fixed expenses and nothing else — that way the Fixed total IS the materials figure your contingency is worked from. Delivery goes under Variable with the consumables.
    3. Put consumables and a contingency line under Variable expenses.
    4. Work contingency as 10% of materials only (paint + primer + timber + fixings). Write it to the nearest cent, then decide with the class whether the whole budget will sit at the nearest cent or the nearest euro.
    5. Read the balance card: are you under the ceiling, about even, or over?

    When the categories, contingency and balance all look right, leave the budget on screen — you will use the same figures in the next step.

    Rebuild the project budget by category

    4 - Hit the Ceiling ~15 mins

    Now lock the arithmetic in with short target puzzles. Each one uses real budget figures as the starter numbers. Build an expression that lands exactly on the target — that is the contingency, a category subtotal, or the grand total under the ceiling.

    Work the first one with the class, then try the rest in pairs. You may use +, −, × and ÷. Do not reuse a starter inside one puzzle unless the prompt says you can.

    Budget totals and contingency

    5 - Record Project Budget V2 ~10 mins

    Your line items only become portfolio evidence once they are grouped, subtotalled, and finished with a contingency line and a grand total. This page is Project Budget v2 — the Collecting stage artefact for MA1 KA1.

    Instructions: Use the prices from your own Project Budget v1 (or the worked school-set figures if you are catching up). Rule the page into the four categories yourself — materials, consumables, delivery, contingency — and complete each one. Show the contingency working, not just the answer. Write every money amount to the nearest cent, then state in the final sentence whether your grand total is to the nearest cent or the nearest euro.

    File the finished page in your Maths Portfolio, named Project Budget v2 — on paper, or as a spreadsheet if you are building it that way.

    Write these down the page, leaving room under each for your answer:

    1. Name at least three categories (for example materials, consumables, delivery) and list every line item under the right one.
    2. Subtotal under each category, with the addition shown.
    3. Contingency as 10% of the materials subtotal only — show the working, not just the answer.
    4. Grand total: every category subtotal plus the contingency line.
    5. Balance against the project ceiling: are you under, level, or over, and by how much?
    6. One sentence stating whether your figures are to the nearest cent or the nearest euro, and using that rule throughout.

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