Sharing Halves

Overview

Lesson 3 of 10 in Sharing Halves and Quarters. Students use one-to-one distribution to split collections of up to 20 objects into two equal groups, then represent and explain the result using drawings or numerals.

Learning intentions

• WALT find half of a group of objects.
• WALT share a collection fairly into two equal groups.
• WALT record how many objects are in one-half.
• WALT explain how I know the groups are equal.

Success criteria

• I can split an even collection into two equal groups.
• I can state how many objects are in one-half.
• I can explain my method using objects, a drawing or words.

Curriculum links

• Mathematics and Statistics — Number: exploring equal sharing and halves through practical collections.
• Mathematics and Statistics — mathematical reasoning and communicating: explaining a strategy and representing thinking.
• Te Mātaiaho Mathematics and Statistics — Mathsteasers: developing higher-order thinking through accessible challenge and problem solving.

Lesson structure (60 minutes)

1. 0–7 min · Welcome and hook. Display the opening question in the sharing hook and learning intention slides: “Two children want to share 8 strawberries fairly. How many will each child get?” Invite children to predict, then share ideas with a partner. Establish that half means one of two equal parts. Students use actions or words to show what “fair” means.

2. 7–17 min · Model equal sharing. Give two hoops or draw two boxes labelled “Child 1” and “Child 2”. Model sharing 6 counters, placing one at a time into each group: “One for you, one for me.” Repeat with 10 counters and count each group. Use the equal-sharing modelling slides to show the collection, each distribution step and the final two equal groups. Students chorally explain why 3 is half of 6 and 5 is half of 10.

3. 17–32 min · Guided practical investigation. Organise pairs with counters and two hoops or paper circles. Display the instructions in the practical investigation slides. Call out or show collections of 4, 8, 12 and, if ready, 16 counters. Partners build each collection, share one counter at a time between two groups, check that the groups match, and say: “Half of __ is __.” The teacher circulates, asks “How did you make it fair?” and photographs or notes effective explanations.

4. 32–47 min · Independent recording. Distribute the halves of collections worksheet. Children solve pictorial problems by first building each collection with counters, then drawing two equal groups and recording how many are in one-half. Begin with collections to 10; children ready for more complete problems to 20. Read every question aloud, highlight the important number, and accept drawing, circling, numerals, oral explanation or a photograph of practical work as evidence.

5. 47–55 min · Share and compare methods. Show the discussion prompts in the reasoning and discussion slides. Invite two or three children to explain a solution, including one practical and one drawn representation. Ask: “How can we check the groups are equal?” and “Would the same method work for 18?” Students turn and talk, then compare whether counting, dealing one at a time or drawing helped them.

6. 55–60 min · Plenary and check. Return to the opening problem using the plenary and exit prompt slide. Students show or say half of 8, then complete the oral exit prompt: “Half of __ is __ because __.” Quickly check one recorded example or ask each child to demonstrate with four counters before packing away.

Resources

• the complete sharing-halves slide deck
• the halves of collections worksheet
• Counters or small classroom objects, at least 20 per pair
• Two hoops, paper circles or drawn group spaces per pair
• Whiteboard and markers
• Pencils, crayons and highlighters
• Optional device or camera for photographing practical evidence

Assessment

• Observe whether students distribute one object at a time and create two equal groups. Note who needs support to count or match the groups.
• Listen for accurate use of “half”, “equal” and “fair”; ask individual students to justify one answer rather than only naming it.
• Use the final oral prompt and worksheet evidence to identify students ready for collections to 20 and those who need further work with collections to 10.

Differentiation

• Support: begin with collections to 10; provide ten-frames, two clearly marked group spaces, counters and a peer or teacher partner. Model the sentence frame “Half of __ is __ because both groups have __.”
• Allow drawing instead of writing, oral explanations, pointing, or a photograph of completed practical work. Do not require formal division notation.
• Dyslexia-friendly practice: read all problems aloud, highlight key numbers, use large uncluttered print and colour-coded group spaces, and provide manipulatives before recording.
• Extension: solve half-of problems to 20, including 14, 16, 18 and 20, then create a matching story problem such as sharing fruit or toys fairly. Ask the student to explain how they checked the answer.