Ozobots are small line-following robots that respond to coloured codes by changing their direction of movement, their speed, or the colour of the LED on top

This series of challenges emphasizes the following Computational Thinking skills:

• Evaluation – determining the optimal way to use lines and colour codes to communicate with the ozobot by assessing and debugging each attempt
• Abstraction – representing complex behaviour as a series of coloured squares
• Logical reasoning – “if I use this code, the ozobot will behave this way”
• Decomposition – in the final challenge, a complex path must be constructed from simpler parts.

### Objectives

• Using markers and paper, students will progress through a series of challenges that explore how to use simple colour codes to program a small robot to respond in a variety of ways.

### Materials

• General supplies:
White paper (at least a few sheets per group of students)
Chisel tip markers in black, red, green, and blue (make sure the markers are quite bright as darker colours will not be read by the Ozobots – we recommend the Ozobot markers or Crayola chisel tips)
Charging cords or charging hub.

• Per group of 2-3 students:
Ozobot Bit (Need a class set? If your’re close enough to retrieve equipment from Science World, we have classroom kits available for lending out to local teachers! Sign up for access here.)

### Key Questions

• Which challenge was easy?
• Which challenge was difficult?
• Did Ozobot always do what you expected?

### What To Do

Ozobot Safety Notes:

• No water/drinks near Ozobots
• No running near or with Ozobots
• Lift the Ozobot up when moving it. Do not push Ozobots along table/carpet (it will break the Ozobot motors) or allow them to “spin their wheels” while running into the wall, etc.

• Ensure Ozobots are fully charged at the beginning of the activity. Ozobots take about 30-40 minutes to fully charge.
• Have spare sheets of paper available to hand out. Encourage trying multiple things on one sheet of paper.
• Calibrate each ozobot: Have the sheet with the black calibration dot ready. Hold the power button on the Ozobot down for two seconds until the top LED flashes white. Quickly place the Ozobot in the middle of the black calibration dot and let go. If the calibration is successful, the Ozobot will move and then blink green. Start over if the robot blinks red. Robots need to be calibrated once at the beginning of each session
• Students should work in pairs or groups of three.
• Each pair or group should start with one Ozobot, colour code sheets and calibration dot, a piece of white paper, and one black marker.

Activity:

Hand out the Ozobots and ask students to locate the following features: on/off switch, optical sensors, wheels.
Tip: Introduce colours after students are comfortable with drawing lines. Colour codes have to be added as an interruption to the black line, they cannot go over the top of a black line.

Hand out the first two challenge cards to students.

• Challenge 1  Follow the Line: Draw a path for your ozobot to follow
• Challenge 2 – Speed up or Slow Down: change the speed of your ozobot using one extra colour

Once students have successfully demonstrated their solution to Challenge 2, you may wish to allow the groups of students to continue at their own pace

• Challenge 3 – Right or Left: Tell your ozobot which way to turn at an intersection.
• Challenge 4 – Stop! Tell your ozobot to stop without touching it.
• Challenge 5 – Crazy Path: Create a path with at least four codes

### Other Resources

Science World  |  Field trip workshops and outreach programs  | Tech Up

Ozobot | more challenges and games for ozobot

Ozobot has a thriving educator community and plenty of resources

Survivors

Artist: Jeff Kulak

Jeff is a senior graphic designer at Science World. His illustration work has been published in the Walrus, The National Post, Reader’s Digest and Chickadee Magazine. He loves to make music, ride bikes, and spend time in the forest.

Egg BB

Artist: Jeff Kulak

Jeff is a senior graphic designer at Science World. His illustration work has been published in the Walrus, The National Post, Reader’s Digest and Chickadee Magazine. He loves to make music, ride bikes, and spend time in the forest.

Comet Crisp

Artist: Jeff Kulak

Jeff is a senior graphic designer at Science World. His illustration work has been published in the Walrus, The National Post, Reader’s Digest and Chickadee Magazine. He loves to make music, ride bikes, and spend time in the forest.

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Artist: Michelle Yong

Michelle is a designer with a focus on creating joyful digital experiences! She enjoys exploring the potential forms that an idea can express itself in and helping then take shape.

Buddy the T-Rex

Artist: Michelle Yong

Michelle is a designer with a focus on creating joyful digital experiences! She enjoys exploring the potential forms that an idea can express itself in and helping then take shape.

Geodessy

Artist: Michelle Yong

Michelle is a designer with a focus on creating joyful digital experiences! She enjoys exploring the potential forms that an idea can express itself in and helping then take shape.

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Artist: Ty Dale

From Canada, Ty was born in Vancouver, British Columbia in 1993. From his chaotic workspace he draws in several different illustrative styles with thick outlines, bold colours and quirky-child like drawings. Ty distils the world around him into its basic geometry, prompting us to look at the mundane in a different way.

Western Dinosaur

Artist: Ty Dale

From Canada, Ty was born in Vancouver, British Columbia in 1993. From his chaotic workspace he draws in several different illustrative styles with thick outlines, bold colours and quirky-child like drawings. Ty distils the world around him into its basic geometry, prompting us to look at the mundane in a different way.