Designing the Esky

Overview

In this fourth lesson of the unit, students move from initial needs and research into early design development by producing clear design sketches and selecting appropriate materials. They will justify their choices using properties, sustainability considerations, and practical constraints.

Learning intentions

Students will:

• analyse a specific need for an esky design and translate it into a usable design brief element
• generate and refine design sketch options for an esky layout, lid, insulation approach and external frame
• investigate and select materials, systems and components using evidence about properties and sustainability
• develop and apply design criteria to evaluate their design idea and make an informed next step

Success criteria

Students can:

• create 2–3 labelled sketch concepts that show the main parts (base, sides, lid, insulation, fastening, handle/drain) and how they work
• explain why selected materials suit the required properties (e.g. insulation, durability, water resistance, stiffness)
• identify at least two sustainability factors affecting material and process selection
• use design criteria to justify which sketch concept is most likely to work and what they will improve

Curriculum links

• AC9TDE10P01: analyse needs or opportunities; develop design briefs; investigate and select materials, systems, components, tools and equipment
• AC9TDE10P04: develop design criteria independently including sustainability to evaluate design ideas, processes and solutions
• AC9TDE10K06: analyse and make judgements on how material properties can be combined to create designed solutions
• AC9TDE10K01 (contextual link): analyse how design and technologies occupations consider ethical, security and sustainability factors

Lesson structure (60 minutes)

1. 0–5 min · Quick recap and success lens Teacher briefly reviews the unit aim and the esky need (keep contents cool, safe handling, durability, cost limits) and displays today’s criteria. Students recall their previous research notes and circle what matters most in the design brief.

2. 5–12 min · Mini-teach: sketching + evidence-based selection Teacher models how to turn requirements into sketch elements and how to justify material choices using properties (not brand names), including one sustainability lens (life cycle thinking). Students annotate a sample sketch with arrows for function and write two “property to requirement” links (e.g. insulation property → heat transfer requirement).

3. 12–25 min · Design brief check (class-to-self) Teacher guides students to restate their chosen target user/need and confirm constraints (size, transport/weight, expected use, budget, available tools). Students complete a short “brief element” sheet: function statements and constraints, then list candidate materials from the class resource set (or teacher-provided options).

4. 25–40 min · Sketching challenge: 2–3 concepts Teacher sets a timer and emphasises clear technical communication: orthographic style or simple labelled perspective; show lid method and insulation placement. Students produce 2–3 sketch concepts in their design journal, each with labels for materials/components and a short “what I’m optimising” note.

5. 40–50 min · Material properties investigation (stations) Teacher runs fast stations using material samples/cards: students match properties to likely performance (thermal/insulation, water resistance, compressive strength, ease of forming, recyclability/renewability, availability). Students rotate (or work in pairs at one station) and record evidence-backed judgements: “Material A chosen because… / might fail if…”

6. 50–56 min · Evaluate with criteria + choose a direction Teacher introduces a simple criteria list (3–5 points) and shows how to score/justify without redesigning everything. Students select one concept and complete a short evaluation against criteria (including sustainability) and note one improvement for the next lesson.

7. 56–60 min · Exit ticket and tidy Teacher collects exit tickets and gives a final reminder of expectations for neat, labelled diagrams and honest justification. Students submit: chosen sketch concept, two material-property justifications, and one sustainability factor.

Resources

• Student design journals or A3/A4 sketch sheets
• Design brief sheet from earlier lessons (or teacher-prepared template)
• Coloured pencils/textas, ruler, eraser
• Material sample set or printed material cards (insulation options, outer shell options, fasteners/adhesives, moisture barriers)
• Criteria checklist template (teacher-prepared)
• Station resource labels showing key properties (e.g. thermal insulation, water resistance, strength, formability, end-of-life)
• Timer and display for timeboxing
• Teacher model sketch (on board or print)

Assessment

• Formative: teacher circulates during sketching to check that students link design elements to the brief (function + constraints) and that labels are clear.
• Formative: station notes are checked for evidence-based property reasoning and at least one sustainability consideration.
• Summative-for-now (exit ticket): chosen concept + justification using at least two material properties and one sustainability criterion.

Differentiation

• Support: provide sentence starters for justification (e.g. “I chose ___ because it has ___, which helps to ___.”) and a partially completed criteria table.
• Support for sketching: offer a template frame showing where lid, insulation layer and outer shell should be drawn; allow students to trace the base outline lightly.
• Extension: students add an alternative material swap (“If insulation fails, I would change to…”) and include a brief risk/contingency note for manufacturing.
• EAL/SEN: reduce the cognitive load by limiting required concepts to two sketches, while maintaining clear labels; allow oral explanation captured by teacher on a checklist.

Exit ticket (collect at 60 minutes)

• Which sketch concept did you choose? (brief description)
• Two materials you selected and the properties you used to justify them
• One sustainability factor you considered
• One improvement you will make next lesson