Flashing Wheels Lesson 2
In this lesson students design their flashing wheel solution for their user.
- Computing: Algorithms, pseudocode, logical thinking, decomposition, abstraction, iteration, loops, selection, testing, debugging, user needs, evaluation
- Science: The heart
- PSHE: Healthy mind and body
- Design and Technology: Product design
Skills: Designing, creative thinking, problem solving, prototyping, team working, presenting.
It is assumed that you have first completed the safety introductory lesson and Flashing Wheels Lesson 1.
In this lesson students design their flashing wheel solution for their user. They create a paper prototype, including a detailed algorithm showing how it will work. Depending on your students’ experience, this may take more than one lesson.
- To design a flashing wheel light solution to meet a user’s needs
- To create a paper prototype
- To write a detailed, accurate algorithm using pseudocode
- To include iteration, loops and selection in algorithms
- To test and debug algorithms
- Introduction (5 minutes)
- Sarah’s flashing wheels (5 minutes)
- Designing user solutions (10 minutes)
- Paper prototype (10 minutes)
- Algorithm design (15 minutes)
- Testing and refining algorithms (10 minutes)
- Wrap up (5 minutes)
- Invite students to recap their user personas from last lesson.
- Introduce that in this lesson students will design their flashing wheels solution to meet their user’s needs (slide 2) and introduce the criteria (slide 3).
- Share the learning objectives if you wish on slide 4.
Sarah’s flashing wheels
- Remind students of Sarah’s user persona (slide 5) and as a class make a list of requirements for Sarah (slide 6) and come up with some ideas for solutions (slide 6)
Designing user solutions
- On rough paper ask students to create a list of potential ideas for solutions, similar to those on slide 6
- Give out large pieces of paper and pens and explain they will be creating a prototype of their chosen solution (slide 7), firstly using the paper and then with micro:bit.
- Ask them to consider what might need to go on a simple paper prototype (slide 8), give them additional materials if needed and time to create their prototypes.
- Once students have got their basic paper prototype, explain they will now design the algorithm for their flashing wheel device, using pseudocode (slide 9). There is a simple example algorithm on slide 10 (which repeats indefinitely) and a more accurate one on slide 11.
- Highlight they will be using iteration, loops and selection (slide 12). Depending on your students’ experience, you may need to spend additional time explaining some of the algorithm/programming concepts
- Ask them to write their initial algorithm on rough paper so they can test and debug it before transferring a final version to their paper prototype.
Testing and debugging algorithms
- Remind students of the criteria (slide 13) and ask them to self and peer evaluate against this to ensure their solution meets the criteria.
- Ask students to work with another pair/team and go through their algorithms, helping each other to evaluate, test and debug their algorithms as necessary.
- Once they have a final, accurate version, they can add this to their paper prototype.
Lesson wrap up
Invite students to stick their paper prototypes and user personas on the wall and have a showcase of their work so far. Explain that next lesson they will use their algorithms to create a micro:bit prototype. If you wish, revisit the learning objectives (slide 14).
Extension / homework
Students could also create flowchart algorithms if you wanted to extend their understanding (see Night Sensor resource). They could write up their work so far in a blog or to form part of an assessment portfolio.
- Encourage the creation of simply yet effective solutions and an algorithm using everyday language rather than pseudocode if necessary. You could also give out text instructions and ask them to sequence them into the correct order for their algorithm.
Stretch & challenge:
Students can create more involved solutions and detailed, accurate algorithms with additional elements from the outset (e.g. can they include music?). They could also be challenged to create a flowchart.
Opportunities for assessment:
- Informal, or more formal assessment if wished, of students’ solutions, algorithms and paper prototypes.