Shape Changes Forces

Overview

In this lesson, students explore how pushes and pulls can change the shape of soft materials such as playdough and balloons. They will describe forces using strength and direction, make simple predictions, then compare observations to what they expected.

Learning intentions

• WALT describe pushes and pulls by naming their strength (big/small) and direction (left/right, up/down, towards/away).
• WALT investigate how a push or pull can start/stop motion and change an object’s shape.
• WALT pose a simple question and make a prediction about what will happen to shape.
• WALT communicate observations using everyday and scientific vocabulary (e.g. push, pull, shape, stretched, squashed).

Success criteria

• I can tell if my force is a push or a pull and describe its direction.
• I can say whether my push/pull was stronger or weaker and describe what changed in shape.
• I can make a prediction and later compare it with what actually happened.
• I can record results using a simple before/after drawing or photo sorting (malleable material set-up).

Curriculum links

• Science — AC9S1U03: describe pushes and pulls in terms of strength and direction and predict the effect on objects’ motion and shape.
• Science — AC9S1I01: pose questions to explore observed simple patterns and relationships and make predictions based on experiences.
• Science — AC9S1I06: write and create texts to communicate observations, findings and ideas, using everyday and scientific vocabulary.
• Science — AC9S1I04: sort and order data and information and represent patterns, including with provided tables and visual or physical models.

Lesson structure (45 minutes)

1. 0–5 min · Hook (see–think–say). Teacher shows a playdough “before” and “after” example (already slightly squashed vs stretched), asks: “What force could make this happen?” Students point to the change and say one idea using a stem: “I think it was a push/pull.”

2. 5–12 min · Mini-lesson: push vs pull + direction. Teacher demonstrates two actions: pushing playdough flat (direction: down/forward) and pulling a balloon outward (direction: away). Emphasise strength words: small/big. Students repeat together using hand motions: “push—small/big” and “pull—away/towards,” then label the direction with one teacher-provided arrow card.

3. 12–22 min · Investigation 1: Squash a lump (shape change). Teacher sets up: playdough lumps on plates; students plan one prediction: “If I push it harder, it will… (stay same / squash more).” Students test two rounds (small push, big push), one partner applies the force while the other watches and records “before/after” with drawings or two quick photos, using a simple table (Small push / Big push).

4. 22–32 min · Investigation 2: Pull and stretch (elastic change). Teacher provides stretchy balloon or putty strip; demonstrates a gentle pull then a bigger pull, reminding students to keep the material safe and controlled. Students test two rounds (gentle pull vs strong pull) and record: what changed in shape (stretched, longer, thinner) and whether they could get back to original shape.

5. 32–39 min · Compare prediction and observation. Teacher facilitates a short whole-group discussion: “Did our shape match our prediction?” and “What direction was the force?” Students use the class sentence frames: “My prediction was… / What happened was… / The force was a (push/pull) to the (left/right/up/down).”

6. 39–45 min · Exit ticket: one-force explanation. Teacher gives a quick worksheet or card with a before/after drawing of playdough or balloon. Students complete one sentence: “I used a ___ to change the shape by ___.” Teacher collects cards as evidence of accurate vocabulary and force description.

Resources

• Playdough, modelling plates or trays
• Small balloons (or stretchy putty/soft foam strips if balloons not available)
• Paper towels and wipes
• Recording sheet with a simple before/after box and two rows (small/big)
• Sentence starter cards: “I predict…”, “I observed…”, “The force was…”
• Arrow cards (left/right, up/down, towards/away)
• Scissors/colour pencils or a tablet for photo sorting (optional)
• Safety reminders posters (gentle handling, no throwing)

Assessment

• Observation checklist during investigations: correct use of push/pull language and ability to state direction and strength.
• Formative check during discussion: students compare prediction with observation using sentence frames.
• Exit ticket: one written/recorded explanation identifying the force and the shape change.

Differentiation

• Support for emerging communicators: use more sentence frames and picture word banks (push, pull, squashed, stretched, stronger/weaker).
• Support for students needing extra structure: provide pre-drawn before/after outlines and limit to two choices (small/big) for strength.
• Extension: for students who finish early, ask an extra question: “What would happen if the direction changed (up instead of down)?” They can test one extra quick trial if time allows.
• EAL/SEN considerations: allow oral responses with teacher scribing; use gestures (push hands forward, pull hands apart) and consistent arrow cards to reduce language load.