Intermediate
60 mins
Teacher/Student led
+65 XP

Time and Date Data

Enter and format dates and times correctly in spreadsheets. Calculate hours worked with a formula, display the result as a readable number, add a total and a TODAY() stamp, and build a practical work-hours tracker for Work Experience or your Something Real project.

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    1 - Introduction ~5 mins

    Welcome

    Dates and times are proper data types in a spreadsheet, not just text that looks like a clock. Once they are entered correctly, you can calculate hours on a shift and how long a Work Experience week really runs. That is the skill behind a timesheet an employer or supervisor can trust.

    By the end of this lesson, you will be able to:

    • Enter and format dates and times correctly
    • Calculate hours worked with a formula and display the result as a readable number
    • Build a work-hours tracker with a total and a TODAY() stamp for Work Experience or your Something Real project

    Warm-up

    Think of one real block of time from your project or Work Experience: a placement day, a shift, a training session, or an event set-up. In your head, note the start time, the end time, and roughly how many hours that was. You will turn that kind of record into a working spreadsheet today.

    2 - Key Concepts ~5 mins

    Three ideas unlock today's tracker. Read the table, then check the worked sample so you know what done looks like.

    ConceptWhy it mattersExample
    Real date — a calendar date the spreadsheet can sort or compare (not typed words) The sheet must see a real date, not words, or later maths and stamps break Type 03/03/2026 for a Work Experience start. Wrong looks left-aligned like plain text; right looks like a proper date
    Real time — a clock time entered with a colon (09:00), so the sheet can do maths with it End time minus start time only works when both cells are true times, not text such as 9-00 A Centra stocktake shift from 09:00 to 13:30 becomes hours with one formula
    Hours formula — {{formula:=(end-start)*24}}, then format the result as Number Multiply by 24 to get hours you can read. Format as Number (not Time) or you may see 04:00 or a tiny decimal instead of 4 {{formula:=(D2-C2)*24}} on a timesheet row, then Number format so the cell shows 4.00

    Worked sample: five placement rows

    Your finished tracker will look like this shape (use your own dates, places, and times):

    DateLocationStartEndHours
    03/03/2026Work Experience: reception09:0013:004.00
    04/03/2026Work Experience: stockroom09:3014:004.50
    05/03/2026Project set-up10:0012:302.50
    06/03/2026Work Experience: phones09:0015:006.00
    07/03/2026Project follow-up11:0013:002.00
    Key point

    Column E uses a formula, not typed numbers. A total row under the five entries adds the hours automatically. You will also stamp the sheet with {{formula:=TODAY()}} so it shows when you last checked it.

    3 - Step-by-step Task ~20 mins

    Build a small sample hours tracker with five rows of date and time data, a formula for hours worked, Number format so hours read clearly, a total, and a TODAY() check. Use the sample placement data first so every formula is proven before you switch to your own Work Experience or Something Real project times.

    4 - Common Issues ~4 mins

    Common Issues

    IssueSolution
    Hours show as a tiny decimal or as a clock time like 04:00 instead of 4.00 Select the Hours cells (including the total), set the number format to Number with 2 decimal places (not Time), and keep the formula as end minus start, then multiply by 24
    A date will not work with TODAY() or looks wrong Re-enter the date as a real date value and apply a Date number format. If the cell is left-aligned plain text, the sheet is not treating it as a date
    End minus start gives a negative number, or the cell shows ##### ##### usually means the column is too narrow or the result is invalid. Widen the column, check that end is later than start on the same day, and that both cells use a Time format with a colon (09:00 not 9-00)

    5 - Independent Practice ~15 mins

    Independent Practice

    Your goal: Turn the sample tracker into a real hours log for Work Experience or your Something Real project so you can prove time spent with formulas, not guesswork.
    Time: ~15 minutes
    Task: Open the cloud workbook {{code:sm3_time_tracker}} in {{code:09_specialism/sm3}} (browser file name only, no extension). Replace the five sample rows with at least five real sessions from Work Experience, placement hours, project work, training, or event set-up. Keep the Hours formula, Number format, the total, and the TODAY() stamp working. Use dates and times that match your actual week where you can. If you have no placement this week, log five realistic Something Real, training, or project set-up blocks with invented but plausible Irish dates and times, and keep the formulas. Each Location cell should name the place or task in a way a supervisor would recognise (for example "Centra: deli counter" or "PA Task: poster print run"), not just "work" or "project".
    Success criteria:
    • {{code:sm3_time_tracker}} sits in {{code:09_specialism/sm3}} as a cloud workbook (no file extension) with clear headings and at least five real rows
    • Hours calculate automatically when you change a start or end time and display as plain numbers such as 4.00
    • A total hours figure and a TODAY() checked-on date are visible on the sheet
    • A supervisor could read the log cold and see when you worked and for how long
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