Multiplying two-digit numbers by multiples of 10: a lesson plan

When students first meet the operation of multiplying a two-digit number by a multiple of ten, the work feels like a brand-new chapter in their maths journey. The shift from single-digit products to tasks such as 36 × 40 or 73 × 60 relies on place value understanding built across the early primary years. Teachers in Australian classrooms recognise this moment as a key checkpoint towards confident multi-digit calculation.

The lesson sits within the Number and Algebra strand of the Australian Curriculum for Year 4 and Year 5. Aligned to the achievement standards, it reinforces the importance of recognising the role of zeros, estimating reasonable answers, and using efficient mental strategies. Schools preparing students for NAPLAN will find that this fluency supports the arithmetic demands of the numeracy test.

A practical way to ground the lesson is to invite students to solve problems drawn from everyday Australian life. Calculating the cost of family tickets to a Saturday AFL match in Melbourne, working out how many minutes it takes to drive 250 kilometres down the Hume Highway, or counting the total number of Tim Tams for a school fundraising stall all bring the mathematics to life. Each scenario provides a reason to multiply by 10, 20, 50, or 100.

This lesson plan offers a teaching sequence for a maths block, a guided group rotation, or a distance education package for regional students learning through the School of the Air. It includes warm-up prompts, modelled examples, practice questions, partner tasks, and a reflection prompt.

Learning objectives and curriculum links

By the end of the lesson, students will multiply any two-digit number by a multiple of ten using written and mental methods. They will explain the role of place value in sliding digits one column to the left, and use estimation to check that answers are reasonable.

The plan aligns with content descriptors from the Australian Curriculum v9, covering the representation of problems using number sentences, efficient calculation strategies, and the connection between multiplication and the array model. It also supports general capabilities such as literacy, through the language of factors and products.

For EALD learners or students needing scaffolding, the objectives can be scaled to focus on recognising multiples of ten and verbalising the operation. Extension learners can move quickly to multiplying three-digit numbers by multiples of one hundred later in the week.

Materials and preparation

Teachers will need a printed worksheet pack for each student, base-ten blocks or place-value charts, mini whiteboards, and a projector for the modelled segment. Counters or MAB blocks are useful for kinesthetic learners who need to push digits physically.

Prepare a few real-world price tags written in Australian dollars. A 200-gram block of cheese at $1.90 per 100 grams, a packet of biscuits at $4.20 per pack, or a bundle of pencils at $3.50 per student all give authentic contexts. Have a "what would you buy?" list ready for the partner task.

If you would like a printable version of the worksheets, answer key, and reflection sheet bundled together, you can find the complete pack through the Heaps O'Wins journal. The download includes a black-and-white master, a coloured version, and a teacher edition with worked solutions.

Step-by-step lesson sequence

Open the lesson with a five-minute mental routine. Display single-digit multiplications beside multiples of ten and invite students to call out the answers. Move from 4 × 6 to 4 × 60, and from 7 × 8 to 7 × 80, drawing attention to the pattern of one extra zero each time.

Model the first two-digit example on the board using the place-value chart. Write 23 × 30 and show how the three in the tens place shifts because of the extra zero, producing 23 × 3 tens. Work through 23 × 3 = 69, then read the answer as 69 tens or 690. Repeat with a second example, asking students to talk through the steps with a partner.

Move students into guided practice with four scaffolded questions on the worksheet. Each includes a place-value chart, an array model, and a number line so learners can choose a representation that suits them. Listen for the language students use and prompt them to say "times three tens" rather than "times thirty".

Independent practice covers eight mixed questions, followed by a word problem section where students write their own number sentences for two scenarios. Allow ten minutes, then gather the class for a quick sharing of strategies before differentiation.

Differentiation strategies

For students needing extra support, provide a hundred grid and highlight the row or column being multiplied. Counting by tens reinforces the structure of the operation and removes the cognitive load of remembering the zero. Visual learners benefit from watching the digits physically move across the place-value chart.

For students working at grade level, introduce estimation as a checkpoint. Ask them to round the two-digit number to the nearest ten, multiply by the multiple of ten, and compare the estimate to the actual product. This builds the habit of reasonableness that supports later work with larger numbers and decimals.

For extension learners, challenge them to apply the strategy to multiplying by 100 or to two-digit multipliers such as 33 × 40. A short investigation asking how many metres a bus travels in forty trips around a Brisbane CBD route of 2.5 kilometres offers a rich context. Advanced students can also explore the distributive property by splitting the two-digit number first.

Assessment and extension ideas

Use the final four questions on the worksheet as a quick formative check. Look for accuracy, correct use of place value language, and whether students are choosing efficient strategies. A short exit ticket asking students to explain how multiplying by 40 is the same as multiplying by 4 captures understanding in just a few sentences.

For follow-up lessons, revisit the skill within a problem-solving context. Students can plan a fundraising stall at a school fete, working out how much money the class will raise if they sell items at multiples of ten cents. They can also measure the distance between Australian capital cities and convert the result into total minutes at a constant speed.

Add a daily quick-fire round to your morning maths meeting across the week. Two questions per day on the board give every student a chance to practise and let the teacher monitor fluency. By Friday, most learners will be multiplying two-digit numbers by multiples of ten with confidence.

Download the full printable pack today, including worksheets, answer keys, and a bonus activity set, and give your students a strong foundation in multi-digit multiplication. Visit the Gialdini Worksheets library to explore hundreds of maths resources aligned with the Australian Curriculum.