systems approach to designing
4 detailed 50-minute lessons with teaching scripts, worked examples, parent guides, and assessment criteria.
Lesson Overview
Total Lessons: 4
Tier: Foundation and Higher
Duration: 50 minutes per lesson (200 minutes total)
Exam Boards: AQA, Edexcel, OCR, Eduqas, CCEA
Tier: Foundation and Higher
Duration: 50 minutes per lesson (200 minutes total)
Exam Boards: AQA, Edexcel, OCR, Eduqas, CCEA
Learning Objectives
- Explain the key ideas of systems approach to designing
- Apply systems approach to designing to exam-style questions
- Develop independent study skills
- Build cross-topic connections
Prerequisites
- Read the revision notes for systems approach to designing first (GCSE Revise summary)
- Key vocab to pre-teach: D&T Exam Tips
- Basic skills: reading the summary notes and answering the practice questions there
Materials & Equipment
- Exercise book, coloured pens
- Ruler
- Printed revision notes (link below)
- Internet for videos (see Resources)
Lesson 1: Introduction: systems approach to designing
Duration: 50 minutes
Starter Activity (5 minutes)
Quick Recall
Write down everything you already know about systems approach to designing. Then check against the key terms: D&T Exam Tips. Use a mini-whiteboard or paper.
Main Content (35 minutes)
Parent/Teacher Guide:
Before lesson: Read the script below. Pre-teach key vocab: D&T Exam Tips.
If stuck: Re-read the revision notes (link above), then break the content into smaller steps.
Extension: See the Stretch & Challenge ideas in Lesson 4.
Before lesson: Read the script below. Pre-teach key vocab: D&T Exam Tips.
If stuck: Re-read the revision notes (link above), then break the content into smaller steps.
Extension: See the Stretch & Challenge ideas in Lesson 4.
Teaching Script (35 mins):
Mins 0-5 - Hook: "Today: systems approach to designing. By the end you will be able to answer exam questions on it unaided. It connects to the rest of Design and Technology because the ideas here recur across the spec."
Mins 5-20 - Direct Instruction: Work through the core ideas below one at a time; after each, ask your student to explain it back in their own words.
Mins 20-30 - Guided Practice: Model the worked example together, then let your student attempt the first practice question with guidance.
Mins 30-35 - Independent Practice: 2-3 practice questions from Lesson 3 below, with immediate feedback.
Mins 0-5 - Hook: "Today: systems approach to designing. By the end you will be able to answer exam questions on it unaided. It connects to the rest of Design and Technology because the ideas here recur across the spec."
Mins 5-20 - Direct Instruction: Work through the core ideas below one at a time; after each, ask your student to explain it back in their own words.
Mins 20-30 - Guided Practice: Model the worked example together, then let your student attempt the first practice question with guidance.
Mins 30-35 - Independent Practice: 2-3 practice questions from Lesson 3 below, with immediate feedback.
First Look
Start with the revision notes summary, then attempt: Explain the difference between an open-loop and a closed-loop system, giving an example of each.
Plenary (5 minutes)
Check Out
Your student states one thing they learned and one question they still have about systems approach to designing.
Lesson 2: Core Concepts: systems approach to designing
Duration: 50 minutes
Starter Activity (5 minutes)
Review Previous Lesson
Quick recap: write 3 key points from Lesson 1 on systems approach to designing. Check them against the notes below.
Main Content (35 minutes)
Key Fact: Systems approach: breaking down a product into interrelated subsystems — input (sensor/switch), process (microcontroller/logic), output (actuator/display).
Key Fact: Open-loop system: no feedback — output does not affect input. E.g. a toaster with a timer: it runs for a set time regardless of how brown the bread is.
Key Fact: Closed-loop system: uses feedback to adjust output — e.g. central heating with a thermostat senses temperature and switches the boiler on/off to maintain the set point.
Key Fact: Feedback: information about the output fed back to the input to adjust the process — essential for precision and consistency.
Key Fact: Flowcharts and systems diagrams: visual tools to represent how subsystems connect — standard symbols (oval=start/end, rectangle=process, diamond=decision, parallelogram=input/output).
D&T Exam Tips: For systems questions, always: 1) State whether open or closed loop, 2) Identify input-process-output, 3) If closed loop, describe the feedback mechanism, 4) Explain why the system type is appropriate for the context. This structure covers AO1–AO3.
| Term | Meaning | Example |
|---|---|---|
| Open-loop | None | Timer-based watering |
| Closed-loop | Negative | Central heating thermostat |
| Bang-bang | On/off | Oven thermostat |
| Proportional | Continuous | Industrial temperature control |
| Microcontroller | Programmable | BBC Micro:bit projects |
| PLC | Industrial | UK food packaging lines |
Practice (10 minutes)
Q: Explain the difference between an open-loop and a closed-loop system, giving an example of each.
Answer: Open-loop: no feedback — the system does not monitor its own output. E.g. a fan heater with a simple on/off switch runs at fixed power. Closed-loop: feedback adjusts the output. E.g. a fan heater with a thermostat senses room temperature and adjusts power to maintain the desired temperature.
Plenary (5 minutes)
Explain Back
Your student teaches the key points back to you without looking. Fill any gaps immediately.
Lesson 3: Application: systems approach to designing
Duration: 50 minutes
Starter Activity (5 minutes)
Quick Recall
Recall the key terms: D&T Exam Tips. Define each in one sentence.
Main Content (35 minutes)
Parent/Teacher Guide: Let your student attempt each question alone first, then compare with the model answer. Award method marks for correct working even if the final answer is wrong.
Q1: Explain the difference between an open-loop and a closed-loop system, giving an example of each.
Answer: Open-loop: no feedback — the system does not monitor its own output. E.g. a fan heater with a simple on/off switch runs at fixed power. Closed-loop: feedback adjusts the output. E.g. a fan heater with a thermostat senses room temperature and adjusts power to maintain the desired temperature.
Q2: A washing machine uses sensors to detect load weight and water temperature. Draw a systems diagram and explain how feedback is used.
Answer: Input: load sensor, temperature sensor, water level sensor. Process: microcontroller compares sensor data with programmed settings. Output: motor speed, water valve, heater control. Feedback: temperature sensor feeds back actual water temperature; microcontroller adjusts heater to reach target. Load sensor determines cycle time — heavier loads need longer.
Q3: Why is a closed-loop system more suitable than an open-loop system for controlling a greenhouse irrigation system?
Answer: A greenhouse needs precise moisture levels: too little water kills plants, too much causes root rot. Closed-loop: soil moisture sensor provides feedback, microcontroller activates irrigation only when moisture drops below threshold. Open-loop: timer-based watering regardless of soil conditions — wastes water in rain, underwater in drought. Closed-loop is essential where conditions vary.
Plenary (5 minutes)
Error Review
Review any questions answered incorrectly. Identify whether the error was knowledge, method, or reading the question.
Lesson 4: Exam Practice: systems approach to designing
Duration: 50 minutes
Starter Activity (5 minutes)
Command Words
Review what these command words require: state (one point), describe (say what happens), explain (say why), compare (both sides), evaluate (judgement).
Main Content (35 minutes)
Extended Answer
Extended question: Full-Mark Response Design a closed-loop system for an automatic greenhouse ventilation system. Explain the input, process, output and feedback, and justify why a closed-loop approach is necessary. <div class="
A grade 9 response will: define input (temperature sensor and humidity sensor inside greenhouse), process (microcontroller compares readings with set points — e.g. 25°C and 60% RH), output (motor opens roof vents, fan activates), feedback (continuous sensor monitoring — when temperature drops below set point, vents close, fan stops); explain why closed-loop is needed (external temperature fluctuates, solar gain varies, open-loop timer cannot respond to actual conditions); discuss safety features (vent limit switches, alarm for sensor failure) and energy efficiency (vents use natural convection before activating fans).
Exam Tips: Always draw a systems diagram if asked — it clarifies your thinking and earns marks | Label input, process, output and feedback clearly | Use the correct flowchart symbols in diagrams
Common Errors: Watch Out! Students often make mistakes here. Wrong: A closed-loop system is always better than an open-loop system because it has feedback. Correct: Closed-loop systems are more precise but also more complex, expensive and potentially less reliable (more components can fail). Open-loop is appropriate where conditions are predictable and precision is not critical — e.g. a simple nightlight that turns on at dusk needs no feedback. Choose the simplest system that meets the requirements.
Stretch & Challenge (Grade 8-9):
- Synoptic links: explain how systems approach to designing connects to another Design and Technology topic you have studied
- Real-world: research one real-world use or example of systems approach to designing
- Critical: "What are the limitations of the models used in systems approach to designing?"
Plenary (5 minutes)
Assessment Criteria
- Got it: Confident explanation + correct worked examples
- Getting there: Main points OK, needs support with detail
- Not yet: Confused on key concepts - re-run Lesson 2
Homework & Consolidation
- Consolidation: Re-answer any Lesson 3 practice questions answered incorrectly (20 mins)
- Retrieval: Write flashcards for the key terms: D&T Exam Tips (10 mins)
- Exam practice: One past-paper question on systems approach to designing from the board websites (15 mins)
- Extension: Explain systems approach to designing to someone else in your own words (10 mins)