CS106AHow Computing WorksFoundational45 min

Programming: Your First Instructions

How you tell a computer, which understands nothing, exactly what to do, step by literal step.

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Big Idea

How Computing Works

Grade bands

K-2 · 3-5 · 6-8 · 9-12

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How AI works · Ethics

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Lesson overview

How you tell a computer, which understands nothing, exactly what to do, step by literal step. This module climbs from an everyday intuition to the real mechanism, then names the Stanford course it descends from.

Teacher script · ~45 min

0–5
Hook
A computer is not clever. It follows instructions literally, in order, with zero common sense. If you tell it to put on your shoes before your socks, it will. Programming is the skill of giving instructions so precise that a thing with no judgment still gets it right.
5–15
Explore
Students do the activity in pairs: On paper, keep a box called 'total' starting at 0. Go through a list of prices and each time add the price to the box. You just ran a loop over a variable — the core of every spreadsheet and app.
15–30
Explain
A CONDITIONAL lets a program choose: IF the answer is right, say 'yes,' OTHERWISE say 'try again.' A FUNCTION is a named recipe of steps you can reuse by name instead of rewriting it. Real programs are mostly these four pieces — variables, loops, conditionals, functions — combined. DECOMPOSITION is the actual skill: splitting a big task into small pieces each of those can handle.
30–40
Connect to the summit
Show students this is the real thing professionals build: A real first programming course. How you tell a computer, which understands nothing, exactly what to do, step by literal step.
40–45
Check
Run the formative check below. Anyone who can explain a key term in their own words has it.

Student activity

On paper, keep a box called 'total' starting at 0. Go through a list of prices and each time add the price to the box. You just ran a loop over a variable — the core of every spreadsheet and app.

Slides

1Title: Programming: Your First Instructions

2Hook: A computer only does exactly what you say

3Do it: Store a thing, then repeat a thing

4How it works: Decisions, and naming your recipes

5Key idea: Variable

6Key idea: Loop

7Key idea: Conditional

8From the summit: CS106A at Stanford

Formative check

1.In your own words, what is "Variable"? (Looking for: A named box that holds a value you can read or change later.)
2.In your own words, what is "Loop"? (Looking for: Telling the computer to repeat steps without rewriting them each time.)
3.In your own words, what is "Conditional"? (Looking for: A fork in the road: do one thing IF something is true, else do another.)

Carry-away concepts

Variable: A named box that holds a value you can read or change later.
Loop: Telling the computer to repeat steps without rewriting them each time.
Conditional: A fork in the road: do one thing IF something is true, else do another.
Function: A named recipe of steps you can reuse by calling its name.
Decomposition: Breaking a big task into small steps a computer can each handle.

From the summit · the Stanford source

The real first course: you write working programs from scratch — variables, loops, conditionals, functions — and learn to break any task into steps a machine can follow without ever guessing what you meant.

This module descends from CS106A at Stanford. Students who climb the full ladder arrive here.

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