Combining Materials

Overview

Students investigate safe simulations of ways materials can be combined to make useful objects. The lesson respectfully recognises Aboriginal and Torres Strait Islander Peoples as diverse knowledge holders with sophisticated technologies; students do not copy cultural objects or replicate sacred or culturally restricted tools. Local community consultation is recommended before teaching culturally specific examples. Students compare joining methods, make predictions and communicate observations.

Learning intentions

Students will:

• recognise that materials can be physically changed or joined without becoming a completely new material
• explore weaving, hafting-style joining and gluing as ways to combine materials
• make and test predictions using a simple fair test
• observe, record and share findings using scientific vocabulary
• describe how science helps people use materials for daily purposes and to reduce waste

Success criteria

• I can describe how materials were changed or joined.
• I can predict, observe and record what happens.
• I can use words such as weave, attach, flexible and strength.
• I can explain which joining method worked best and give evidence.

Curriculum links

• Physical changes to materials, including bending, twisting, stretching, breaking and joining, without changing material composition.
• Using science in daily life, including observations and patterns to make predictions.
• Suggesting and following safe investigation procedures.
• Comparing predictions, observations and others’ findings, and considering whether a test was fair.
• Creating texts to communicate observations, findings and ideas using everyday and scientific vocabulary.

These links reflect the Western Australian implementation of the Australian Curriculum content descriptions for Year 2 Science. The relevant learning objectives include the supplied descriptors for physical changes, science in daily life, investigation safety, comparing findings and communicating observations.

Lesson structure (60 minutes)

1. 0–8 min · Welcome, respect and intention. Teacher opens with the welcome and cultural respect slides, acknowledging Aboriginal and Torres Strait Islander Peoples as diverse knowledge holders and explaining that people have long used careful observation and material knowledge to make useful objects; teacher states, “Today we use safe classroom simulations, not copies of cultural objects.” Students share one way people join materials at home and help establish rules: respect, no tasting, gentle testing and ask before using equipment.

2. 8–16 min · Explicit modelling. Teacher uses the materials and modelling slides to demonstrate over-under weaving, wrapping and taping a foam object to string, and applying equal amounts of paste and PVA to overlapping paper strips. Explain: bending, twisting, stretching and joining physically change materials, but do not necessarily make a completely new material. Model the vocabulary: material, combine, join, weave, haft/hafting, attach, fibre, string/thread, glue, strength, flexible, predict, test, fair test and observe. Students identify one variable that must stay the same in a fair test.

3. 16–40 min · Rotating investigations. Teacher places students in three groups of 8–9 and starts each rotation with the station instruction slides; groups spend approximately eight minutes at each station, with one minute to rotate. Students record predictions and observations on the materials investigation recording sheet.

• Station 1: Weaving. Setup: paper strips or raffia, a pre-cut paper loom, trays and blunt-ended scissors if trimming is needed. Students weave over-under, pushing strips together to make a small mat or panel. Prompts: “What happens when the strips cross?” “Is the panel more or less flexible?” “Where is it stronger?” Expected observations: the strips remain paper or fibre, the panel may hold its shape better, and tighter weaving can make it harder to pull apart. Students carry strips carefully and keep raffia away from faces and mouths.

• Station 2: Hafting/joining simulation. Setup: lightweight foam balls or soft stone-shaped objects, string/thread, masking tape and rubber bands. Students wrap and attach the object to the string, using a simple knot only if suitable and supervised. They gently lift or pull with teacher guidance. No sharp stones, blades, sticks or throwing. Prompts: “Which attachment feels secure?” “Does wrapping spread the force?” Expected observations: several wraps, tape or a rubber band may hold more securely than one loose loop, but results can vary.

• Station 3: Glue investigation. Teacher prepares flour paste: mix 2 tablespoons flour with approximately 3 tablespoons water, adjusting to a smooth paste. Do not taste; check allergies and hygiene. Use teacher-prepared PVA with its safety guidance: do not taste, avoid eyes, wash hands and report spills. Students join equal-sized paper strips using equal glue amounts, the same overlap and the same drying time, then perform a gentle pull test. They complete a table: Glue | Prediction: stronger/weaker | Observation after drying | Result. Expected results may vary; PVA will often form the stronger bond after drying, while flour paste may be weaker or more flexible.

4. 40–45 min · Clean-up and safety check. Teacher signals stop, checks that glue is closed and materials are returned, then disposes of paste hygienically. Students wash hands, clear stations and place recording sheets in the collection tray.

5. 45–55 min · Sharing and discussion. Teacher displays the comparison and discussion slides and invites one observation from each station. Ask: “Did your prediction match your result?” “Were all tests fair?” “What had to stay the same?” “How might joining materials help people reuse things and reduce waste?” Connect respectfully to Aboriginal and Torres Strait Islander technologies as diverse examples of skilled material selection and combining, without naming or reproducing restricted objects. Students compare results with another group and use evidence to explain the strongest method.

6. 55–60 min · Reflection and exit ticket. Teacher shows the reflection and exit-ticket slide. Students complete orally or in writing: “I changed or joined ___ by ___. I observed ___. The best method for ___ was ___ because ___.” Collect responses and invite two students to share.

Resources

• the complete investigation slide deck
• the materials investigation recording sheet
• Paper strips, pre-cut paper looms or raffia
• Foam balls or soft stone-shaped objects
• String/thread, masking tape and rubber bands
• Flour, water, containers, spoons and paper strips
• Teacher-prepared PVA glue, trays and wipes
• Aprons, handwashing supplies and station cards
• Timer, pencils and collection tray

Assessment

• Use an observation checklist: identifies a material; follows safety steps; makes a prediction; uses a joining method; records an observation; compares results.
• Ask during stations: “What changed?” “What stayed the same?” “How could we make this test fair?” Listen for accurate use of vocabulary and safe procedures.
• Assess the exit ticket for recognition that materials remain the same type after physical joining, a clear observation and evidence-based comparison.

Differentiation

• Support with picture-labelled station cards, teacher modelling, pre-started weaves, larger materials, partner recording and sentence starters: “I predicted…”, “I observed…”, “It was fair because…”.
• Provide oral recording, scribing, enlarged print, non-latex bands and assistance with fine-motor tasks; ensure allergy, sensory and hygiene needs are checked.
• EAL/D learners may rehearse vocabulary with a partner and draw results before writing.
• Extend learners by asking them to redesign one joining method, explain which variable they changed, and suggest a further fair test using a different material.