1 - Introduction ~5 mins
On screen: a live project budget with one cell open in edit mode (cursor fixing a misspelled item) and Undo ready on the toolbar. That calm fix-and-reverse habit is what you build today.
Welcome
You already have {{code:05_project_budget}} with real items for your Something Real project. Today you learn how to fix cells without wrecking the rest of the data, reverse a mistake in one click, and grow the sheet safely when costs change mid-week.
| Today's safety kit | Why it protects your budget |
|---|---|
| Edit mode | Change one letter without wiping the whole cell |
| Clear versus delete | Empty a wrong value without removing a whole row |
| Undo / Redo | Reverse a bad paste or fill before it spreads |
By the end of this lesson, you will be able to:
- Edit cells safely using edit mode, and choose clear versus delete correctly
- Use Undo, Redo, Copy, Paste and fill-drag without losing data
- Find and fix mistakes in a sample sheet and in your own budget
- Add five new rows, edit three existing rows, and confirm your budget is still intact
Warm-up
Think of the last time you typed over a whole cell by accident and wiped what was there. What would you want a spreadsheet to do next: panic, or let you reverse the last action instantly?
2 - Key Concepts ~5 mins
Three safety habits keep a live budget usable. Read these, then you will practise them on a short starter sheet your teacher has shared.
| Concept | Why it matters | Example |
|---|---|---|
| Edit mode — double-click a cell (F2 on Windows/Chromebook; Ctrl+U on Mac in Excel Online) so you change part of the text instead of replacing the whole cell | Stops you wiping a long note when you only meant to fix one letter | Changing "Bussiness cards" to "Business cards" in a promo line without retyping the whole note |
| Clear versus delete — clear empties a cell's contents; delete can remove the whole row or shift other cells | Clearing is usually safe; deleting a row can throw out a cost you still need | Clearing a wrong € amount in Cost is fine; deleting the whole Materials row by mistake is not |
| Undo and Redo — reverse or replay the last action with keyboard shortcuts or the toolbar arrows | Your safety net when a paste or fill goes wrong | You clear the wrong cell; Undo brings the old value back in one step |
Copy/Paste and fill-drag come next inside the practice steps, with a short tip just before you use each one.
3 - Step-by-step Task ~16 mins
Open the short practice budget your teacher shared (errors already planted). Rehearse edit mode, clear versus delete, Undo/Redo, Copy/Paste and fill-drag. This file is for learning only. Your real portfolio work comes next on {{code:05_project_budget}}.
Mid-task checkpoint: after the Undo practice, you should still see Packaging bags in the sheet. If not, ask for help before you continue to Copy/Paste.
4 - Common Issues ~4 mins
Common Issues
| Issue | Solution |
|---|---|
| I typed over a cell and the old text vanished | Press {{kbd:Ctrl+Z}} (Windows/Chromebook) or {{kbd:Cmd+Z}} (Mac) immediately. Next time, double-click the cell (or use F2 on Windows/Chromebook, or Ctrl+U on Mac in Excel Online) so you edit inside it instead of replacing it. |
| A whole row disappeared when I pressed Delete | You may have used Delete row from the right-click menu. Undo once. To empty one cell only, click the cell and press Delete/Backspace without choosing a row command. |
| Fill-drag copied the wrong number down the column | Undo the fill. Enter 1 and 2 in the first two cells, select both, then drag the fill handle again. If a mini menu appears in Excel Online, choose Fill Series, not Copy Cells. On a trackpad, type the next numbers by hand or ask for a quick demo of the fill handle. |
| Copy/Paste landed in the wrong place | Undo, click the exact target cell, paste once. Avoid pasting while a whole column is selected unless you mean to fill that column. |
5 - Independent Practice ~20 mins
Independent Practice
- File is still named {{code:05_project_budget}} in the {{code:05_budget}} folder (not {{code:editing_practice_temp}}). Check the title at the top before you finish
- Your budget has five new item rows with Item, Category, Cost and Notes filled for your Something Real project
- At least three older rows show a clear improvement (corrected text, updated cost, or cleaner note)
- No accidental blank holes, missing earlier rows, or half-pasted cells; the sheet is still easy to scan top to bottom
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