Computer Science Unplugged
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Colour by Numbers: Image Representation
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This activity shows learners how computers use numbers to represent pictures. A grid is used to represent the pixels (short for picture elements) of a computer screen.
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You Can Say That Again!: Text Compression
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This activity helps students learn how computers "compress" text by identifying repeating patterns of letters, words, and phrases.
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Card Flip Magic: Error Detection & Correction
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This magic trick is based on how computers detect and correct data errors.
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Sound Representation: Modems Unplugged
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In this activity, learners listen to songs and decode hidden messages based on the same principle as a modem. As a final challenge, learners decode the binary messages in a music video.
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Treasure Hunt: Finite-State Automata
In this computer science activity about finite-state automaton (on page 45 of the PDF), learners use a map and choose various pathways to find Treasure Island.
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Unlocking the Secret in Product Codes
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In this activity, learners will explore how product barcodes are scanned accurately and be able to "guess" the last number in a 13 digit barcode correctly every time.
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Cryptographic Protocols: The Peruvian Coin Flip
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This activity about cryptographic techniques illustrates how to accomplish a simple, but nevertheless seemingly impossible task—making a fair, random choice by flipping a coin between two people who d
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Information Hiding: Sharing Secrets
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This activity about cryptographic techniques illustrates a situation where information is shared, and yet none of it is revealed.
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Guess the Sentence
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In this activity, learners play a game similar to Hangman by guessing a secret phrase to understand how computer scientists measure the amount of "information" in a document.
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Kidbots
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In this activity, one person acts as a human robot while another acts as their developer by programming their actions.