Test the efficiency of two different grabber designs and determine the best one based on specific test criteria.
- 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 (20 Min.)
- Have your pupils work in pairs to build the hand controller and 2 test grabbers.
- Ask them to play the test program to get an idea of how the grabbers work.
4. Explain (10 Min.)
- Have your pupils test their grabbers by grabbing:
o Objects of different sizes but of similar weight (Test #1)
o Objects of different weights but of similar size (Test #2)
- Remind them to note the test results in their test tables.
5. Elaborate (10 Min.)
- Facilitate a class discussion about the test results.
- Ask your pupils to collect objects from around the classroom and to predict which grabber will be the best at grabbing each of them.
- Don't forget to leave some time for tidying up.
- 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 testing by asking relevant questions. Here are a few suggestions:
- Why do people use grabbers to pick up rubbish?
- How might you figure out which grabber is best?
- Have you ever watched online videos of product reviews?
Consider showing an online video of a product review in order to spark engagement.
Have your pupils watch this video to see what they're about to do.
Split each team's building tasks in order to ensure that everyone is actively involved.
- Pupil A: Grabber 1
- Pupil B: Grabber 2 and Controller
Designed to Grab
Grabber 1 has been designed to grab light, flexible objects. Its flexible claw makes it very inefficient at grabbing big, heavy or smooth objects.
Grabber 2 has been designed to grab large, heavy objects. Its split claw makes it almost impossible to grab small objects.
Use Common Objects
For testing, you can use any objects that are readily available. You can even have your pupils select their own objects from around your classroom.
Suggestions for light objects of different sizes:
- LEGO brick (small)
- Crumpled ball of paper (medium)
- Empty plastic bottle (large)
Suggestions for medium-sized objects of different weights:
- Crumpled ball of paper (light)
- Stack of LEGO wheels (medium)
- Apple (or any round fruit; heavy)
Simplify this lesson by:
- Limiting testing to 2 objects (e.g. a big object like a bottle and a small object like a pen)
Take this lesson to the next level by:
- Allowing your pupils to define their own test criteria
- Having your pupils design their own grabbers, then run the tests again using their own designs
- Incorporating the maths or language arts extension(s)
Teacher Observation Checklist
Establish a scale that suits your needs, for example:
- Partially accomplished
- Fully accomplished
Use the following success criteria to evaluate your pupils' progress:
- The pupils are able to identify testing criteria.
- The pupils are able to conduct fair testing.
- The pupils are able to draw conclusions based on their test results and communicate them clearly.
Have each pupil choose the brick that they feel best represents their performance.
- Blue: I've successfully tested one grabber.
- Yellow: I've successfully tested two grabbers.
- Violet: I've successfully tested two grabbers and used my test results to determine the best design.
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
Language Arts Extension
To incorporate the development of language arts skills:
- Have your pupils create a presentation or a video review highlighting the pros and cons of each grabber.
- Ask your pupils to upload their videos to the appropriate channels, use comments as feedback.
Note: This will require additional time.
To incorporate the development of maths skills:
- Introduce the concept of a weight factor as a way of evaluating objects. For example, effectiveness could be measured according to a weighted-criteria of: 25% aesthetics, 20% cost, 5% portability and 50% weight. Explain that the sum of all weight factors should add up to 100%.
- Have your pupils score each grabber (-1 or +1 point) for each of these extra criteria and then apply the weight factors.
Note: This will require additional time.
The pupils who enjoyed this lesson might be interested in exploring these career pathways:
- Agriculture and Horticulture (Horticultural Science)
- Business and Finance (Entrepreneurship)
- Manufacturing and Engineering (Pre-Engineering)
The pupils will:
- Define evaluation criteria for 2 designs
- Test 2 designs using objects of different shapes and sizes
- Make recommendations regarding the best design
LEGO® Education SPIKE™ Prime Set
Empty plastic bottle
Ball of crumpled paper
Apple (or an object of equivalent weight)
CAS Computing Progression Pathways
Recognises that different solutions exist for the same problem. (AL) (AB)
Recognises that different algorithms exist for the same problem. (AL) (GE)
Uses criteria to evaluate the quality of solutions, can identify improvements making some refinements to the solution, and future solutions. (EV)
Designs criteria to critically evaluate the quality of solutions, uses the criteria to identify improvements and can make appropriate refinements to the solution. (EV)