Grade All Grades • 60 minutes

Created by Caitlin Davey on 30/3/17


In this activity, students will imagine that they are Chris Hadfield remotely controlling the Canadarm 2 from on board the International Space Station. Students will use computational thinking processes (breaking down a problem, looking for patterns, developing algorithms) and their prior coding experience with Scratch to create a simulation in which they become the controller of Canadarm2 to put a new module on the International Space Station.

Prep Work

Check our Teacher Guide for tips and tricks! 

Review the sample Scratch project to see what students will be building.

The Lesson

This lesson was made in partnership with

Thumb chrishadfieldThumb lets talk science 


We’ve built a series of tutorial videos to help you learn how to teach Canada Learning Code lessons! Each lesson is broken down into its own video tutorial and accompanies the step by step instructions on the lessons page.

Resources Thumb historica canada logo

Learn more about Chris Hadfield in this interview:


Building the International Space Station (ISS) is no easy task! The crews of the ISS have to attach have to attach modules weighing tons, extend solar panels longer than a bus, and haul equipment to and from the space shuttle. 

Canadarm2 is a Canadian-made robotic arm located on the International Space Station (ISS) that helped astronauts such as Marc Garneau and Chris Hadfield build the ISS in space. Since 2001, the 17-metre long Canadarm2 has been helping move equipment, supplies, astronauts, and even spacecraft such as SpaceX’s Dragon capsule around the ISS.

In the International Space Station (ISS) actions have to be done in the correct order in order to place modules where it needs to go on the ISS. It will be a “lock & key” fit, so that the piece must go on properly in order for it to work.

  • Have students share what they already know about the International Space Station and the Canadian robotic devices used there (i.e., Canadarm2, Dextre). This could be facilitated through a Write-Around Discussion learning strategy or a class discussion.
  • Explain to the students that Canadarm2 is a Canadian-made robotic arm located on the International Space Station (ISS) that helped astronauts such as Marc Garneau and Chris Hadfield build the ISS in space. Since 2001, the 17-metre long Canadarm2 has been helping move equipment, supplies, astronauts, and even spacecraft such as SpaceX’s Dragon capsule around the ISS.
  • Watch Hadfield behind the controls of Canadarm2
  • After watching the video, as a class discuss questions such as:
    • In what ways is the Canadarm2 used on the International Space Station?
    • Where is a good place to go to control the Canadarm2?
    • Why are there so many cameras to help guide the astronaut when controlling the Canadarm2?
    • What are some of the limitation of using a robot such as the Canadarm2?


Using Scratch students will imagine that they are controllers of Canadarm2, like in the video of Chris Hadfield.

Before creating any scripts in Scratch, have each pair of students discuss and plan the sequence of movements that will enable the grappling hand of the Canadarm2 to travel from its starting location to grab each of the modules from the payload bay of the space shuttle.
Students should use written instructions such as “turn 90⁰ counterclockwise” drawings to convey the sequence of movements and actions.

Have each group show and explain to you the sequence of movements on paper. Then they can work on the Scratch version of the task.

  • Review the project Sprites and backgrounds. Click on the ‘arm’ sprite to begin. This sprite has 3 scripts that allow it to extend grab modules and return to add them to the ISS. The first script we’ll make sets the start position and costume for the arm. It starts with events when green flag clicked, sets the costume with the looks switch costume block, and the position with a motion go to block. 

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  • The next two scripts control the arm moving up and down. Both scripts begin with an events block when key pressed and have a motion change y by block to move the arm either up or down depending on whether the up or the down arrow is pressed. 

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  • We’ll do the same thing for the x coordinates. 

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  • This next script is what controls the arm grasping, opening and closing. To do this, we begin with an events when key pressed block. After this we have a looks switch costume to change the arm to arm open so that the arm looks as though it’s grabbing. Then we have an events broadcast block that sends a message, we control wait, and finally a looks switch costume.   

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  • Switch the the ‘’pentagon’ sprite to add the next set of scripts. For all the shapes we need 3 scripts. In the first script we check for the event when green flag clicked, position the shape using a motion go to. 

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  • In the next script, we have an events when I receive to check for the broadcast. Then, a forever loop. Inside our loop we check if the module is touching the arm. Then, we looks go back 1 layer to appear behind the arm, control wait, and motion go to the arm. This sequence is what allows the module to attach and appear to follow the arm. 

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  • In the last sequence we begin with the event when I receive broadcast block, next we have a control forever loop. Inside our loop this code repeats forever, we have another control if/then block. We are checking IF the shape is sensing touching the correct port. IF it the next sequence is run. In this sequence we have a motion go to block to have the shape go to the correct port, control stop scripts block, and finally a control wait block.

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  • Add the same code for each of the shapes. Test out your game out! How could you extend the game to make it more complex?


  • Assess if students can reflect on Canadians contributions to space. Have students modify and describe the X and Y coordinate within the game. How did the coordinates contribute to the game logic?
  • KWLs can be used as a diagnostic assessment of students’ understanding of the task before the students do the Scratch portion of the activity.
  • Students could create a flowchart or sequence of steps using mathematical language (e.g., turn 30⁰ clockwise, travel forward 3 cm, turn 60⁰ counterclockwise, etc.).


  • How could they keep track of the modules that are collected?
  • Have students add some sound effects to bring their game to life.
  • Have student create additional modules to add to their Scratch game.
  • Have students move the module and/or ports in the Scratch file and repeat the challenge.
  • Have students write a first-person account of an astronaut using the Canadarm2 to successfully capture a Dragon or Cygnus capsule.
  • Watch this video to learn about the 40 years of robotic innovation that Canada has made, including importantly the Canadarm!

Suggested Lessons

Intended Province:


  • Subjects:
  • Technology Education
  • Science

Key Curriculum Concepts

  • Science: Canadian contributions to space exploration
  • Math: geometry - translation, spatial awareness