Shape and Measure

Overview

Today students measure and compare areas in everyday contexts, using informal units first and then formal units. Students also try micro:bits by using a simple “grid walk” to generate square-count area estimates, supporting low-ability learners with a visual, hands-on approach.

Learning intentions

• Students will estimate area using square units and explain whether an estimate is reasonable.
• Students will measure and compare areas of rectangles using square grids.
• Students will connect a physical model (micro:bit grid steps) to the idea that area is “how many squares cover a surface”.
• Students will solve a short everyday area problem and check their answer.

Success criteria

• I can count or estimate the number of squares that cover a shape to find area.
• I can use a correct area unit (e.g. cm²) and label my answer.
• I can compare two areas and justify which is larger and why.
• I can check my area work by using a second method (estimate then count, or count then sanity-check).

Curriculum links

• Mathematics — Area: recognise features of an object associated with area, estimate and measure area using informal and formal units, and apply this to solve problems.
• Mathematics — using strategies and language for measurement and problem solving in context, including comparing values (builds on core maths thinking for Stage 4).
• Right-angled triangle/Pythagoras is not used today; the focus stays squarely on area measurement and comparison.

Lesson structure (60 minutes)

1. 0–5 min · Hook (micro:bit curiosity). Teacher shows the introduction slides and asks, “What do you think ‘area’ means if I cover a page with tiny sticky squares?” Students answer on their mini whiteboards in one sentence or a sketch.

2. 5–15 min · Direct teach: informal to formal area. Using the introduction slides, teacher models counting squares on a grid and relates this to area units: “If 1 square is 1 square-centimetre, then 6 squares is 6 cm².” Students follow along on a blank grid, counting together with the teacher for one worked example.

3. 15–30 min · Micro:bit grid-walk model (guided). Teacher sets up stations with a printed grid board (1 square = 1 cm or 1 “unit square”) and a micro:bit showing a simple step-count mode (teacher demonstrates; students do not need programming knowledge yet). Students take turns: each “step” corresponds to covering one new grid square, and they track total steps = estimated area. Teacher prompts with the introduction slides: “Does the estimate match the square count on the grid? Why/why not?” Students record both their micro:bit step total and the counted squares.

4. 30–45 min · Main task: compare and measure areas. Distribute the area grid worksheet to pairs (or triads). Teacher revisits the introduction slides to read the task checklist: estimate first, then measure by counting squares, then write which area is larger. Students complete questions with support:

• Q1–Q2: count squares to find areas of two rectangles.
• Q3: estimate using halves/near counts, then confirm by counting.
• Q4: a short explanation: “How do you know your answer makes sense?”

5. 45–55 min · Plenary: reasoning and common mistakes. Teacher uses the introduction slides to display 2–3 anonymised student-style solutions (made-up but realistic): one correct, one incorrect with a unit mistake, one with a counting error. Students use “Spot the mistake” thinking: identify what went wrong and correct it. Teacher explicitly targets: unit labelling (cm²), counting full squares only, and confusing perimeter with area.

6. 55–60 min · Exit ticket (quick check). Students complete a 1-minute response on their worksheet: “Which is larger and what is the area? Circle your unit.” Teacher collects the area grid worksheet before dismissal.

Resources

• the introduction slides (hook + worked example + micro:bit demonstration cues + plenary visuals)
• the area grid worksheet (one page; estimation + measurement + short reasoning)
• Micro:bits (enough for small groups), batteries or charging setup, and teacher-prepared step-count display mode
• Printed grid boards (for station use), sticky squares or counters
• Mini whiteboards and markers
• Timer for station rotation
• Student pencils/erasers and ruler (optional)

Assessment

• Formative during hook: brief written/sketch responses on what “area” means.
• Observation during micro:bit station: whether students connect steps to square coverage and correctly record totals.
• Worksheet marking: use a simple rubric for units (cm²), correct counting, and reasonableness explanation.
• Exit ticket: check ability to compare two areas and state area with correct units.

Differentiation

• Support:
• Provide sentence starters on the area grid worksheet: “I know it is larger because…”, “My estimate was… and my measured area was…”
• Use partially completed worked grid examples for students who need a model.
• In micro:bit stations, assign roles: one student counts squares, one records, one operates micro:bit.
• Challenge/Extension (light-touch for mixed ability):
• Ask students to estimate without counting first by using multiplication (length × width) after they’ve done counting, then compare—only if they are ready.
• EAL/SEN considerations:
• Keep wording consistent: “area = how many squares cover the surface”.
• Use visual cues (coloured unit squares, clear “cm²” label) and avoid long instructions.