Measure and Compare

Overview

Students explore length by measuring classroom objects with informal units such as cubes, counters or pop sticks. They build on everyday comparison language—longer, shorter, taller and the same length—and begin to understand that fair measuring requires the same-sized units placed end to end with no gaps or overlaps.

Learning intentions

• WALT compare the length and height of familiar objects.
• WALT measure objects using equal-sized informal units.
• WALT explain how we know which object is longer or shorter.
• WALT record measurements using numbers and simple words.

Success criteria

• I can use words such as longer, shorter, taller and the same length.
• I can measure carefully with equal-sized units.
• I can start at the edge and place units in a straight line without gaps or overlaps.
• I can tell someone what I measured and how many units long it was.

Curriculum links

• Mathematics and Statistics — Measurement: comparing and measuring length using informal units.
• Mathematics and Statistics — Number: counting objects accurately and connecting quantities with numerals.
• Mathematics and Statistics — Mathematical practices: explaining thinking, asking questions and working collaboratively.
• Mathsteasers: developing higher-order thinking through purposeful mathematical challenge and discussion.

Lesson structure (30 minutes)

1. 0–4 min · Engage and notice. Display the mystery measuring hook showing two classroom objects that look different in length, and ask, “Which is longer? How could we prove it?” Students make a quiet prediction, then share with a partner using the words longer or shorter.

2. 4–8 min · Model fair measuring. Use two equal-sized pop sticks to model measuring a book: place the first stick at the edge, continue in a straight line, and count aloud; deliberately show a gap and an overlap for students to judge. Students practise the actions in the air and explain why gaps, overlaps or different-sized units would make the result unfair. Refer to the fair measuring demonstration.

3. 8–11 min · Explain the investigation. Organise 25 students into pairs, with one group of three, and give each pair a small container of identical linking cubes or pop sticks. Distribute the measuring investigation sheet and explain that pairs will choose three safe classroom objects, predict which is longest, measure each object, and record the number of units.

4. 11–22 min · Hands-on measuring investigation. Circulate while students measure objects such as a pencil, book, table edge, whiteboard ledge or shoe; prompt, “Where will you start?”, “Are your units touching?” and “How do you know?” Students take turns as measurer and recorder, then compare their results with another pair. Students may refer to the investigation steps and discussion prompts.

5. 22–27 min · Share and reason. Invite pairs to report one measurement, for example, “The pencil was 7 cubes long.” Record two or three results on the board and ask whether an object could have a different number when measured with larger units. Students explain how using the same unit makes comparisons fair and identify any careful measuring choices they made.

6. 27–30 min · Reflect and check. Show the final reflection questions and ask students to complete the final box on the measuring investigation sheet: draw or write one thing they measured, its number of units, and finish the sentence, “I measured fairly by…”. Collect sheets as students return equipment.

Resources

• the complete measuring lesson deck
• the measuring investigation sheet
• Identical linking cubes, pop sticks or counters
• Small trays or containers for measuring units
• Safe classroom objects of varied lengths
• Whiteboard and marker
• Pencils and crayons
• Floor or table space for partner work

Assessment

• Listen for correct use of longer, shorter, taller and the same length during the hook and partner talk.
• Observe whether students begin at an edge, use equal-sized units, keep units touching and count accurately; photograph or note examples needing follow-up.
• Check worksheets for a sensible prediction, recorded measurement and explanation of fair measuring. During the final discussion, ask selected students to demonstrate how they would correct a gap or overlap.

Differentiation

• Support learners with a visual demonstration left on the board, a reduced choice of two objects and a sentence frame: “The ___ is ___ cubes long. It is longer/shorter than the ___.”
• Pair students strategically and give roles—measurer, recorder and, for the group of three, checker—then rotate roles.
• For learners who need additional motor or attention support, use larger linking cubes, measure short objects on a clear mat and provide adult help with counting.
• Extend confident students by asking them to measure the same object with two different-sized units and explain why the number changes while the object’s length stays the same. Use home-language discussion and gestures before expecting English explanations.