Mathematics
Intermediate
40 mins
Teacher/Student led
+80 XP
What you need:
IWB/Projector/Large Screen

Multiplying Multi-digit Whole Numbers

Learn to multiply multi-digit whole numbers by splitting each factor into place-value parts, using an area model to find partial products, then adding them together for the total.

Teacher Class Feed

Load previous activity

    1 - Getting Started ~4 mins

    Illustration for Getting StartedHere is a question to chew on: 34 × 26. That looks like a hard sum to do in one go. But what if we could break it into easier multiplications and then add them together?

    How could we split 34 and 26 into smaller, friendlier pieces?

    2 - Watch and Notice ~9 mins

    The interactive splits each multiplication into a grid of smaller boxes. Watch how each factor breaks apart along the sides, and how the boxes fill in. Each box is one partial product; we add them all for the total.

    3 - Try It Together ~7 mins

    Now we build one together: 47 × 38. We split each factor into its tens and units — 47 becomes 40 and 7 down the side, 38 becomes 30 and 8 along the top. That makes four boxes, one partial product in each. Fill in each of the four boxes with its partial product, then add them all for the total.

    Build the area model: 47 × 38

    4 - Draw the Grid in Your Copy ~4 mins

    COPYBOOK MOMENT

    In your maths copy, draw the area-model grid for each of these products. Write each partial product inside its box, then add them for the total. Box the final answer.

    • 34 × 26
    • 47 × 38

    5 - Class Challenge ~11 mins

    Today we work through these four products together, each one a step harder: 47 × 38, then 152 × 24, then 263 × 35, then 318 × 46. Split both factors into their place-value parts, fill in every partial product, and add them for the total.

    Find the product by partial products

    6 - What Did We Notice? ~2 mins

    MATHS TALK

    We split factors into place-value parts, but does a different split of the same factors still give the same total?

    Take 34 × 26 two ways.

    Way 1: 30 + 4 and 20 + 6. The four partial products add to 884.

    Way 2: split 34 as 20 + 14 and keep 26 as 20 + 6. New partial products, same total 884.

    Why does breaking a number into different parts never change the answer? When you added all the boxes, did you ever get a different total from a friend who split the numbers a different way? Talk with a partner, then we share.

    7 - What's Next ~3 mins

    What we learned

    • Split each factor into its place-value parts to make easier multiplications.
    • Each box of the area model is one partial product.
    • Add all the partial products for the total — the answer is the same however you split.

    Coming up

    Tip

    Next we use estimation alongside long multiplication, rounding first to check our answers are sensible.

    Pupil practice
    Module 2 · Operations and Computational Fluency Number
    Lesson 15 · Multiplying Multi-digit Whole Numbers
    Download Activity Book page (PDF)
    End of lesson
    123learn · Online learning platform

    Unlock the full learning experience

    You're previewing this lesson. Get full access to this lesson and hundreds more — each one ready to teach, with interactive activities, printable resources and pupil progress tracking built in.

    Hundreds of curriculum-aligned lessons
    Interactive activities in every lesson
    Printable resources & progress tracking
    Copyright Notice
    This lesson is copyright of Coding Ireland 2017 - 2025. Unauthorised use, copying or distribution is not allowed.
    🍪 Our website uses cookies to make your browsing experience better. By using our website you agree to our use of cookies. Learn more