Tens and Ones

Overview

Students build, read and partition two-digit numbers using groups of ten and leftover ones. They connect concrete materials to drawings, numerals and place-value language, building on counting in ones and recognising numbers to 20.

Learning intentions

• WALT build two-digit numbers using tens and ones.
• WALT explain the value of each digit in a two-digit number.
• WALT partition numbers into tens and ones.
• WALT use zero when a number has no ones.

Success criteria

• I can make a number with groups of ten and single ones.
• I can tell how many tens and ones are in a number.
• I can write a number as tens and ones, for example, 34 is 3 tens and 4 ones.
• I can use zero correctly, for example, 50 is 5 tens and 0 ones.

Curriculum links

• Representing whole numbers: use counting sequences of ones and tens flexibly.
• Representing whole numbers: read, write and order two-digit numbers using place value and the role of zero.
• Representing whole numbers: partition numbers to describe and record quantity values.
• Combining and separating quantities: use number bonds and partitioning to reason about quantities.

Lesson structure (60 minutes)

1. 0–7 min · Hook and warm-up. Open with the hook and warm-up slides and display a mystery collection of 26 counters arranged as two groups of ten and six loose counters. Ask, “How could we count this quickly?” Students turn and talk, then count aloud in tens and ones. Briefly rehearse counting forwards by tens: 10, 20, 30, 40, 50.

2. 7–18 min · Explicit teaching. Use the tens-and-ones teaching slides to model 34 with bundled sticks or linking cubes. Place 3 groups of ten and 4 single cubes in a place-value chart. Say, “The 3 is in the tens place, so it means 3 tens, or 30. The 4 is in the ones place, so it means 4 ones.” Record 34 = 30 + 4 and 3 tens + 4 ones. Students copy the actions with their own materials and practise saying the complete sentence.

3. 18–30 min · Guided build and explain. Show 21, forty-five and 50 one at a time using the guided examples. Students build each number with bundles and ones, then record it on mini-whiteboards as tens, ones and a numeral. Pause to discuss 50: it has 5 tens and 0 ones. Check understanding by asking students to hold up the number of tens with their fingers and point to the ones digit.

4. 30–45 min · Partner investigation. In pairs, one student chooses or is given a two-digit number from the range 10–60 and the other builds it with materials. The builder explains, “I made __ tens and __ ones. The number is __.” Partners swap roles and complete the recording tasks on the tens-and-ones practice worksheet. Circulate, asking, “How do you know?” and “What does this digit represent?” Encourage students to regroup ten single ones into one group of ten if needed.

5. 45–53 min · Reasoning challenge. Use the reasoning and challenge slides to present errors such as “47 has 4 ones and 7 tens” and “30 is 3 tens and 3 ones”. Students show agree/disagree signals, correct the statements with materials or drawings, and explain their reasoning to a partner. Invite several students to share precise place-value language.

6. 53–60 min · Plenary and exit check. Return to the plenary slides. Students complete the final questions on the worksheet independently: draw or describe 42 as tens and ones, partition 58, and complete “70 is __ tens and __ ones”. Collect responses and ask two students to explain how they solved one answer.

Resources

• the tens-and-ones lesson deck
• the tens-and-ones practice worksheet
• Linking cubes, pop sticks or counters
• Elastic bands for bundling groups of ten
• Place-value charts labelled tens and ones
• Mini-whiteboards and markers
• Pencils and erasers
• Small number cards from 10 to 60

Assessment

• During modelling, listen for correct use of “tens”, “ones”, “place” and “value”; check that students connect the tens digit with groups of ten.
• During partner work, observe whether students can build, read and partition numbers, including numbers such as 20, 30 and 50 with zero ones.
• Use the final worksheet questions as an exit check. Record students who need further practice with grouping, digit position or zero as a placeholder.

Differentiation

• Support: Work with numbers from 10–30 first, provide a large tens-and-ones chart, and keep concrete materials available. Use sentence frames: “I made __ tens and __ ones”; “The __ means __ tens.” Model each instruction visually and orally.
• Dyslexia-friendly access: Use a clear sans-serif font, large numerals, generous spacing and uncluttered worksheet sections. Read every question aloud, highlight the tens digit in one colour and the ones digit in another, and allow students to answer by building or speaking before writing.
• EAL/D and diverse learners: Pre-teach and repeatedly gesture the words “tens”, “ones”, “group”, “digit” and “value”. Pair students strategically and accept drawings, manipulatives, oral explanations or labelled numerals as evidence of understanding.
• Extension: Ask students to find three different ways to represent 36, explain why 3 tens and 6 ones is the same as 36, or solve, “I have 5 tens and more than 2 ones but fewer than 8 ones. What numbers could I be?” Challenge them to order three chosen numbers and justify their order.

Extension

• Students create a two-digit “mystery number” clue for a partner, such as “I have 4 tens and an even number of ones. I am greater than 42.”
• Students investigate regrouping: show how 29 can become 2 tens and 9 ones or 1 ten and 19 ones, then discuss which representation is most useful.