Broken
Figure out why something isn't working and fix it.
![lesson-header](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltf9b7d72339eea126/5ec96fd5cd4cf750c8893897/lesson-header.png?locale=en-gb&auto=webp&format=jpeg&width=500&quality=90&fit=bounds)
Lesson plan
1. Prepare
- Read through the pupil material in the LEGO® Education SPIKE™ App.
2. Engage (5 Min.)
- Use the ideas in the Ignite a Discussion section below to engage your pupils in a discussion relating to this lesson.
- Use the video to explain the lesson.
3. Explore (35 Min.)
- Have your pupils work in pairs to build the CNC machine, have them keep in mind that they're building a non-functioning machine.
- Ask them to run the program and to try to identify and correct the issues that they see.
- Remind them to document the problems and their solutions.
4. Explain (10 Min.)
- Facilitate a sharing session. Encourage your pupils to talk about the problems they’ve found and the solutions they came up with.
5. Elaborate (25 Min.)
- Ask each team to improve their CNC machine by modifying their build and/or program.
- Have them take turns sharing their improvements with the class.
- Don't forget to leave some time for tidying up.
6. Evaluate
- Give feedback on each pupil's performance.
- In order to simplify the process, you can use the assessment rubrics that have been provided.
Ignite a Discussion
Start a discussion about iteration or fixing things by asking relevant questions. Here are a few suggestions:
- What's usually your first reaction when something breaks?
- What will you do first if you're going to fix something?
- What's the last thing you fixed? How did you find the problem?
- What's a CNC machine? Do you know what it's used for?
Have your pupils watch this video to see what they're about to do.
![lesson-header](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltf9b7d72339eea126/5ec96fd5cd4cf750c8893897/lesson-header.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Building Tips
Partner Build
Split each team's building tasks in order to ensure that everyone is actively involved.
- Pupil A: top of the CNC machine
- Pupil B: bottom of the CNC machine, and needle
![teacehr-2parts](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blt4aaf870498fc43d5/5ec96fa656542b5199dc1592/teacehr-2parts.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Pre-Designed shapes
You can use blank sheets of A4 paper for this lesson, but pre-designed PDFs of CNC cuts are provided. By using these pre-designed sheets, it'll be easier for your pupils to determine whether or not the CNC works.
![teacher-shapes](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blt58bb4e323f469915/5ec96fa4a8bb8c02ad27b170/teacher-shapes.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Loading the Paper
Here's how you load the paper:
![teacher-loading-paper](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blt2922506560728baf/5ec96fa915b57c6108324864/teacher-loading-paper.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Looking for Issues
The CNC machine model has 4 real issues that must be fixed in order for the program to work as it’s meant to:
- A paper feeder wheel is missing, causing the y-axis to not work properly.
- The top of the CNC machine isn't correctly attached to the bottom.
- The paper feeder gears are inverted, causing the paper to enter the CNC machine too quickly.
- The pencil carriage isn't connected, causing the x-axis to work incorrectly.
![teacher-question](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blt2c0dedf6b8a6f6a0/5ec96fa556542b5199dc158e/teacher-question.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Easy Fixes
Here's the easiest way to fix these issues, but keep in mind that the objective of this lesson is for your pupils to find their own solutions.
![teacher-solution](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltefb69f71db8c02ff/5ec96faabdc37e61dc29a7dd/teacher-solution.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Possible Upgrade
Your pupils can upgrade their CNC machines by adding a Colour Sensor.
![teacher-improve](https://assets.education.lego.com/v3/assets/blt293eea581807678a/blt748103de81375c4a/5ec96fa700455b25665b2700/teacher-improve.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Coding Tips
Main Program
Possible Solution
Differentiation
Simplify this lesson by:
- Suggesting a selection of bricks that your pupils can use to fix the issues
- Asking all of the teams to work on the same upgrade so that it's easier to evaluate the improvements
Take this lesson to the next level by:
- Having your pupils draw complex shapes on the printer, including curves
- Having your pupils transform this model into a 3-D printer by adding a z-axis
Assessment Opportunities
Teacher Observation Checklist
Establish a scale that suits your needs, for example:
- Partially accomplished
- Fully accomplished
- Overachieved
Use the following success criteria to evaluate your pupils' progress:
- The pupils are able to describe the function of an object.
- The pupils are able to describe the benefit of an object's features against needs.
- The pupils are able to construct effective arguments.
Self-Assessment
Have each pupil choose the brick that they feel best represents their performance.
- Blue: I can describe how things work.
- Yellow: I can describe in detail how things work, and I can highlight what they do well.
- Violet: I can convince someone that I've invented the coolest thing in the world.
Peer-Assessment
Encourage your pupils to provide feedback to one another by:
- Having one pupil use the coloured brick scale above to score another pupil’s performance
- Asking them to present constructive feedback to one another so that they can improve their group’s performance during the next lesson
![student-06](https://assets.education.lego.com/v3/assets/blt293eea581807678a/bltcc0b396324b5bef3/60bf62841b32a31d5305b93c/student-06.png?locale=en-gb&auto=webp&format=jpeg&width=1800&quality=90&fit=bounds)
Language Arts Extension
To incorporate the development of language arts skills:
- Have your pupils work hands-off to role-play calling a customer support line.
▷ One pupil describes the problem.
▷ The other pupil explains how to fix it.
Note: This will require additional time.
Maths Extension
To incorporate the development of maths skills:
- Have your pupils find the gear ratio of the paper feed.
- Ask them to use appropriate language to describe how it controls the speed at which the paper enters the CNC machine.
- Have them explain (and try) what would happen if the gears were swapped.
Note: This will require additional time.
Career Links
The pupils who enjoyed this lesson might be interested in exploring these career pathways:
- Business and Finance (Entrepreneurship)
- Education and Training (Teaching)
- Media and Communication Arts (Broadcast Technology)
Teacher Support
The pupils will:
- Evaluate the performance of a design solution
- Iterate to find problems and then fix them
LEGO® Education SPIKE™ Prime Set
Pencils
CAS Computing Progression Pathways
Algorithms:
Represents solutions using a structured notation. (AL) (AB)
Programming and Development:
Designs, writes and debugs modular programs using procedures. (AL) (DE) (AB) (GE)
Information Technology:
Makes appropriate improvements to solutions based on feedback received, and can comment on the success of the solution. (EV)