On the desk: a loaf of bread, a jar of peanut butter, a jar of jam, and a knife. At the front: your teacher, who has just become a robot. The robot is strong, tireless, and perfectly obedient — and it has no common sense whatsoever. Your group’s written instructions are all it has. What could go wrong?

The task

Write instructions that get the robot from an untouched desk to a finished sandwich. Write them as a numbered list, exactly as they should be executed, and hand them in — no edits once the run starts. The robot will follow your words with malicious literalness: the most absurd reading your sentence permits is the reading it will get. Groups watch each other’s runs, which is half the lesson.

What tends to surface

Somewhere between the jar on the bread and the knife through the bag, the room discovers what an instruction really is: a sentence that survives its worst reading. Decomposition, precision, the gap between what you meant and what you said — the four moves of Computational Thinking all make their first appearance here, and the everyday routines of Algorithms in Everyday Life suddenly look harder-won than they did yesterday.

An extension

Trade lists with another group and mark them the robot’s way: find the single most literal misreading each instruction allows. Then revise one list to survive it. Version two is always shorter and more precise — worth wondering why.

The answer is not on this page

There is no perfect instruction list printed here, and no two classes produce the same disasters. The class builds the idea of precision together — one absurd sandwich at a time.

Curriculum connection

A1.1

apply computational thinking concepts and practices when planning and designing computational artifacts

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C1.2

describe simple algorithms that are encountered in everyday situations

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