1 - Introduction ~5 mins
Welcome
You already have a working budget with totals and averages. Today you add three more questions your spreadsheet can answer on its own: what is the cheapest line, what is the dearest line, and how many items are actually on the list. Those answers matter when you are deciding what to cut, what to keep, and whether your plan still fits real money.
By the end of this lesson, you will be able to:
- Use MIN, MAX, COUNT and COUNTA for real questions about data
- Choose COUNT versus COUNTA correctly
- Write the right formula for short self-test questions
- Add MIN Cost, MAX Cost and Item Count cells to {{code:05_project_budget}}
Warm-up
Glance at your Something Real budget in your head. Without opening the file, which single cost do you think is the highest? In a few minutes your spreadsheet will prove or correct that guess, and you will not have to scan the column by eye every time the numbers change.
2 - Key Concepts ~6 mins
Four formulas sit beside SUM and AVERAGE. Each answers one question. Watch the COUNT versus COUNTA trap before you touch the sheet.
| Concept | Why it matters | Example |
|---|---|---|
| MIN — smallest number in a range | Finds the cheapest line so you know what barely moves the total | {{code:=MIN(C2:C9)}} might return €6.50 for packaging bags |
| MAX — largest number in a range | Flags the dearest line where a cut frees the most money | {{code:=MAX(C2:C9)}} might return €34.99 for an ink set |
| COUNT — counts numbers only | Tells you how many costs are actually entered; blanks and text are ignored | With one Cost blank, {{code:=COUNT(C2:C9)}} returns 7 |
| COUNTA — counts every non-empty cell | Use for names and labels. COUNT on names returns 0 and looks like “no items” | {{code:=COUNTA(A2:A9)}} returns 8 item names even if a cost is missing |
Craft-stall practice (next step): eight items, costs from €6.50 to €34.99, Business cards Cost left blank on purpose. Expect: lowest €6.50 · highest €34.99 · item names 8 · costs entered 7.
3 - Step-by-step Task ~20 mins
Build a short practice table for a craft-stall cost list, then add MIN, MAX, COUNT and COUNTA summary cells. Leave one Cost blank so COUNT and COUNTA disagree. Your teacher may project the eight rows below, dictate them once, or share a starter sheet so you can move quickly into the formulas. You will apply the same pattern to your own {{code:05_project_budget}} in the Portfolio Build.
| Item | Category | Cost (€) |
|---|---|---|
| Sticker packs | Materials | 12.50 |
| Card stock | Materials | 8.00 |
| Ink set | Materials | 34.99 |
| Stall fee | Venue | 25.00 |
| Social ads | Promo | 15.00 |
| Mailers | Materials | 6.50 |
| Design tool | Tools | 11.99 |
| Business cards | Promo | (leave blank) |
Headings go in row 1 as Item, Category, Cost (€). Data starts at row 2. Business cards is row 9 with an empty Cost cell on purpose.
4 - Common Issues ~4 mins
Common Issues
| Issue | Solution |
|---|---|
| Item count shows 0 even though the list is full | You almost certainly used {{code:COUNT}} on a text column. Switch to {{code:COUNTA}} for names, categories and labels. |
| MIN or MAX looks wrong (too high, too low, or includes a label) | Check the range does not include the header row or a Total row. Use only the data cells, for example {{code:C2:C15}}, not {{code:C1:C16}}. |
| The formula appears as plain text instead of a result | Every formula must start with {{code:=}}. Delete the cell contents and retype, starting with the equals sign, then press {{key:Enter}}. |
| COUNT is lower than the number of rows I can see | That can be correct. COUNT skips blanks and text. If a Cost cell is empty, COUNT will be smaller than COUNTA on the Item column. |
Optional pair check (about 3 minutes): complete the matching worksheet Which formula does which job? with a partner. Hint: if the column holds words (item names), you need COUNTA, not COUNT.
5 - Independent Practice ~15 mins
Independent Practice
If Item count comes back 0, do not delete your list — check you used COUNTA on the names column, the same trap as in practice.
- Main budget sheet (not {{code:Formula_practice}}) shows labelled lowest cost, highest cost, and item count cells
- Each formula range matches your real data block only (no headers or Total row)
- Summary values calculate automatically; changing one cost updates at least one result
- File shows Saved (Excel Online) or All changes saved in Drive (Google Sheets) so your teacher can bank the artefact
6 - Reflection ~5 mins
Think about
- When you compared your guess from the warm-up with MAX on the real budget, what surprised you?
- For your Something Real project, which is more useful right now: knowing the cheapest line, the dearest line, or the item count, and why?
7 - Lesson Summary ~5 mins
What you covered
- I can use MIN and MAX to find the lowest and highest values in a cost list
- I can choose COUNT for numbers and COUNTA for text labels
- I can write the right formula for short “which formula?” questions
- I added MIN Cost, MAX Cost and Item Count cells to {{code:05_project_budget}}
Extension challenge
Add one more useful summary cell of your own choice (for example COUNT of costs still blank, or MAX of one Category only if you can select that block cleanly). Write a six-word note beside it explaining the decision it helps you make for your Something Real project.
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