Discovering Groups of Ten

Overview

In this first lesson of the five-lesson unit, students use concrete materials to make equal groups of 10 and connect each group to a numeral. They build from counting individual objects to recognising that each additional group increases the total by 10.

Learning intentions

• WALT make and count equal groups of 10.
• WALT connect groups of 10 to numerals.
• WALT count forwards in tens to 50.
• WALT explain that each number is 10 more than the previous number.

Success criteria

• I can make a group of 10.
• I can count groups of 10 accurately.
• I can match groups of 10 to the numerals 10, 20, 30, 40 and 50.
• I can explain that the next number is 10 more.

Curriculum links

• Mathematics and Statistics — Number: counting, grouping and representing quantities.
• Mathematics and Statistics — Number: connecting concrete representations with numerals and recognising patterns when counting in tens.
• Mathematics and Statistics — communicating mathematical thinking by explaining how quantities change.
• Mathsteasers: developing higher-order thinking and challenge for advanced learners through mathematical reasoning.

Lesson structure (60 minutes)

1. 0–7 min · Hook and prior knowledge. Teacher displays the hook and learning intention slides and shows a mixed collection of counters, asking, “How could we count these quickly without counting every counter?” Students think-pair-share, estimate how groups might help, and practise counting forwards from 0 to 20.

2. 7–17 min · Model a group of 10. Teacher models placing 10 counters carefully into the ten-frame mats, touching and counting each counter once, then writes 10 beside the completed frame. Students make their own group of 10, check it with a partner and say, “One group of 10 is 10.”

3. 17–30 min · Build and connect groups. Teacher demonstrates adding a second, third, fourth and fifth group of 10, using the group-building and numeral slides to connect the groups with 10, 20, 30, 40 and 50. Students work in mixed-ability pairs: one student builds groups using counters or bundled straws while the other chooses the matching visual number card, then they swap roles.

4. 30–42 min · Count in tens together. Teacher leads the class in touching each group and counting, “10, 20, 30, 40, 50,” pausing to ask, “What changed when we added one more group?” Students count forwards and backwards in tens with actions, identify the number that comes next, and explain that it is 10 more than the previous number.

5. 42–54 min · Independent application. Teacher distributes the groups-of-ten practice worksheet and refers to the guided practice and challenge slides. Students draw or complete groups of 10, match representations to 10, 20, 30, 40 and 50, fill in missing numbers in a counting sequence, and complete the sentence frame: “___ is 10 more than ___.” Teacher conferences with individuals and checks that students are counting groups rather than recounting every object.

6. 54–60 min · Plenary and exit check. Teacher shows one final representation on the discussion and plenary slide and asks, “How many groups of 10 can you see? How do you know?” Students share strategies, then individually respond to: “Draw 3 groups of 10, write the total, and explain what happens when one more group is added.”

Resources

• Counters, linking cubes or other small manipulatives
• Bundled straws, with 10 straws in each bundle
• Visual number cards for 10, 20, 30, 40 and 50
• Ten-frame Mats
• Discovering Groups of Ten slide deck
• Groups of Ten practice worksheet
• Pencils, crayons and mini-whiteboards
• Optional adult-led table for supported counting

Assessment

• Observe whether students create exactly 10 objects in a group and organise them so they can be checked efficiently.
• Listen for accurate counting in tens and explanations using “10 more”; note whether students connect a numeral to the correct number of groups.
• Use the plenary response as an exit check. Record students who can independently represent three groups of 10, identify 30 and explain the increase to 40.

Differentiation

• Support learners with ten-frames, bundled straws, visual number cards and adult-guided counting. Reduce the task to one, two and three groups before extending to 50.
• Use mixed-ability pairs with clear roles: builder, counter, card matcher and explainer. Provide the sentence frames “I can see ___ groups of 10” and “___ is 10 more than ___.”
• For learners who need additional language support, model gestures and repeat the phrases “group of 10”, “total”, “next” and “10 more”; allow responses through pointing, building, drawing or speaking.
• Extend advanced learners by asking them to represent the same total in different ways, such as ten-frames, bundled straws, drawings and repeated addition, then predict the total before counting individual objects.

Extension

• Challenge students to build 40 or 50 in two different ways using groups of 10, explain how they know both representations have the same total, and predict the total when another group is added.
• Ask students to create a missing-number puzzle such as “10, 20, __, 40, __” and explain the pattern to a partner.