What if? is part of a CS Unplugged unit about how computers notice and fix mistakes in the information they store and send. The activities use card tricks and number games.
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Is it for me?
It is for children about 8-10 and up who like puzzles and magic tricks, with a grown-up or teacher to help. It is a Beginner activity and needs no computer.
Grown-ups: practise the trick before you show it. Some activities in this unit use arithmetic, so a calculator is fine.
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How to start
Get a set of two-sided cards or make some from paper.
Try the card trick or number game with a grown-up.
Swap roles, and try to explain why it works.
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How much time?
Most lessons take about 30 minutes. Plan about 25 minutes for a session. (estimate)
25 min per session3 sessionsestimate
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A plan you can follow
Day 130 minLearn the card trick.
Day 230 minShow the trick to a friend or family member.
Week 130 minTry the next activity in the unit.
Week 230 minLook for where mistakes get fixed in real life.
Times are estimates. Go at your own speed.
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Go to the learning site
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From the list: uccser/cs-unplugged · License: CC-BY-SA-4.0 · CS Unplugged: Error detection and correction
Lesson from CS Unplugged, University of Canterbury CSER Group, licensed CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/). Changes were made: translated and level-tagged by Open Cosmos, with AI. Shared under the same license.