Plan a party like a boss
Today no new topic. Today you build: you will plan a birthday party for 8 children — with a shopping list, a budget and a timetable. Exactly this is what adults do when they organise something; they just call it organisation.
You will use almost everything from this level:
- multiplying — how much of what to buy (8 children of 3 canapés…),
- dividing — portions and sharing (sweets into bags…),
- written adding — the sum of prices in the budget,
- estimating — is a five-hundred enough?,
- units — litres of drink, grams of cake, minutes of the programme.
Work on a big sheet, write clearly and leave all calculations visible — a project is not only the result, but also the path to it. When you are 완료, show the plan to your parents. The best praise for a project is when the party is really held from it.
Sofie will have a birthday and mum offered a deal: “Plan it yourself and I will pay — if you fit into 500 crowns.” Sofie takes paper and writes: Ema, Tereza, Adam, Jonáš, Filip and two cousins will come — with her eight children. Each will eat about 3 canapés and drink 2 cups of juice. Plus bags of sweets to say goodbye. Mum peeks over her shoulder and wonders how much maths fits into one party. Sofie calculates on: a budget is a budget.
At each calculation write what it is for (“canapés altogether”, “price of drinks”). In a week you otherwise will not know what which number meant — and parents will not read it at all.
Project plan step by step
We will go through the whole plan. Then you can change the numbers for your own party.
1. Guests: 8 children.
2. Food (multiplying): each eats 3 canapés → 8 × 3 = 24 canapés. Grandma’s tray makes 30 → one tray is enough, 6 left as a reserve.
3. Drink (multiplying + units): each drinks 2 cups of 250 ml → 8 × 2 = 16 cups → 16 × 250 ml = 4 000 ml = 4 litres. We buy juice in two-litre packs → 4 ÷ 2 = 2 packs.
4. Goodbye bags (dividing): a bag has 50 sweets, there are 8 children → 50 ÷ 8 = 6, remainder 2. Each bag gets 6 sweets, 2 are left (the birthday child eats them, that is the law).
5. Budget (written adding + estimate): ingredients for canapés 129 Kč, juices 89 Kč, sweets and bags 245 Kč. Estimate: 130 + 90 + 250 = 470 — it should fit into 500, but tightly. Exactly under each other: 129 + 89 + 245 = 463 Kč. We fitted, reserve 37 Kč.
6. Timetable (time): party 14:00–17:00 → 3 hours. Games 1 h 30 min, cake and food 45 min, presents 30 min → together 2 h 45 min, 15 min reserve left for greeting.
Budget under each other
Prices: 129 Kč, 89 Kč, 245 Kč.
Estimate first: 130 + 90 + 250 = 470. Limit 500 → it should come out.
In writing: I add the first two: 129 + 89: ones 9 + 9 = 18, I write 8, one on; tens 2 + 8 + 1 = 11, I write 1, one on; hundreds 1 + 1 = 2. Subtotal 218.
I add the third: 218 + 245: 8 + 5 = 13, I write 3, one on; 1 + 4 + 1 = 6; 2 + 2 = 4. Altogether 463 Kč.
Compare with the estimate: 463 against 470 — same league. And 463 < 500: the budget holds.
Drink in litres
I need 16 cups of 250 ml.
Step 1: millilitres altogether: 16 × 250. I split: 16 × 250 = 16 × 25 × 10. And 16 × 25 = 4 × (4 × 25) = 4 × 100 = 400. So 4 000 ml.
Step 2: convert: 4 000 ml = 4 l (divided by 1 000).
Step 3: packs of 2 l: 4 ÷ 2 = 2 packs.
If 5 l came out, I need 5 ÷ 2 = 2, remainder 1 → three packs. A remainder in shopping rounds up — you do not leave thirsty guests.
Afternoon timeline
Party 14:00 to 17:00.
How much time do I have? From 14:00 to 17:00 → 3 hours = 180 minutes.
Programme: games 1 h 30 min (90 min), food and cake 45 min, presents 30 min.
Sum: 90 + 45 + 30 = 165 minutes = 2 h 45 min.
Reserve: 180 − 165 = 15 minutes for greeting and delays.
Schedule: 14:00 greeting, 14:15 games, 15:45 food and cake, 16:30 presents, 17:00 end. Each time comes from adding the length of a block — check it in pieces through whole hours.
Do not plan with no reserve! Extra canapés, leftover sweets from dividing, 15 minutes free, a few crowns under the limit — leftovers and reserves are not a mistake in the plan, they are its cushions. A plan stretched to the limit bursts at the first change.
Practice: now you do it 🎲
Now try it for real. You will see all the questions at once, like on paper. 시작 with ten. When it goes well, add more.
Budgets add under each other — practise so the party fits to the crown.
Your project
A big sheet, a pencil and your own numbers. This is your party.
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Decide the base: how many guests (a different number than 8 is fine), a budget limit, from when to when. Write it at the top of the paper.
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Work out food and drink: portions per guest times the number of guests, convert drink to litres, decide the number of packs. Write all calculations visibly.
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Build a budget: list 3–5 items with prices (estimate from a shop if you like), make an estimate and then an exact sum under each other. Compare with the limit.
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Build a timeline from arrival to the end and share sweets into bags by dividing (with a remainder for the birthday child). Show the finished plan to your parents.
Now you 💪
- You have all four parts on paper: guests, food and drink, budget, timetable.
- The budget has an estimate and an exact sum under each other and it fits into the limit.
- Each calculation has a label of what it is for.
Done when: You have a finished party plan with visible calculations, a budget under the limit and a timeline with a reserve.
What to take from this lesson
- A big task is solved in parts: guests, food, budget, time.
- Multiplying plans shopping, dividing portions, adding under each other the budget.
- An estimate before the exact sum watches that you can even fit into the limit.
- Leftovers and reserves are the plan’s cushions, not mistakes.
- A calculation with a label you will read even in a week — without a label it is just a number.
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