Your classroom

Python, one lesson at a time

16 lessons and 6 hands-on labs. Read a short lesson, take the quiz, then open the code editor right under the lab and write real Python — auto-graded in your browser.

Lessons

Labs

Total

258m

Done

0/22

Start: Printing & your first program

unit 01

Hello, Python

0/4 done

Write your first lines of code and make the computer talk back.

Printing & your first programMake Python speak: your very first line of code. · 7 min Declaring variablesGive a value a name so you can use it again later. · 8 min Numbers & mathWhole numbers, decimals and the seven operators you will use constantly. · 8 min

unit 02

Strings & booleans

0/4 done

Work with text, then learn how Python answers yes and no.

What is a string?Text, length, joining and the f-strings you will use every day. · 8 min String methods & slicingClean text up, pull pieces out of it, and search for patterns. · 10 min Booleans & comparisonsTrue, False, and how Python decides which is which. · 7 min

unit 03

Making decisions

0/3 done

Teach your program to choose between paths.

If, else — letting your code decideRun a block of code only when a condition is true. · 9 min elif, and, or, notMore than two paths, and conditions that combine. · 9 min

unit 04

Lists & loops

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Hold many values at once, then do something with each of them.

Lists: many values in one placeStore, read, add and reorder a collection of values. · 9 min For loopsDo something once for every item — the pattern behind almost everything. · 10 min While loops & loop controlRepeat until something changes, and know how to break out. · 10 min

unit 05

Functions & collections

0/3 done

Package your logic, then store data by name instead of position.

FunctionsName a block of code, give it inputs and get a value back. · 11 min Dictionaries & setsLook values up by name, and keep only the unique ones. · 11 min

unit 06

Leveling up

0/4 done

Errors, your own types, and functions that call themselves.

Errors & exceptionsCatch problems instead of crashing, and read the messages Python sends. · 10 min Classes & objectsDesign your own type, with data and behaviour together. · 12 min RecursionSolve a problem by solving a smaller version of it. · 11 min

Where this path leads

The same ground the freeCodeCamp scientific computing curriculum covers: variables, strings, booleans, conditionals, lists, loops, functions, dictionaries, sets, errors, classes and recursion — through to regular expressions and building small tools of your own.

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