What Is a Function?
A function is a reusable set of steps.
What Is a Function? is a free Coding for Kids lesson on CoddyKit — lesson 1 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Coding for Kids learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
A Magic Recipe
Hi explorer! 🧑🍳 Today we learn about functions.
A function is like a recipe. It is a group of steps you save so you can use them again and again!
Why Recipes Help
Imagine making a sandwich. 🥪
- Get the bread
- Add cheese
- Close it up
If you write these steps once, you can make a sandwich any time without thinking hard!
Doing It Over and Over
Without a recipe, you would explain every step every single time. So tiring! 😴
A function lets you say one short word and all the steps happen. Like magic! ✨
A Function in Python
In Python a recipe looks like this. The word def means "I am making a recipe".
Run it and see the friendly hello! 👋
def say_hello():
print("Hello, friend!")
say_hello()The Name of the Recipe
See the part say_hello? That is the name of our recipe.
You pick the name yourself, just like naming a pet! 🐶
Calling the Recipe
Writing say_hello() is called calling the function.
It means: "Hey recipe, do your steps now!" 🎬
def say_hello():
print("Hello, friend!")
say_hello()
say_hello()Use It Again and Again
Look! We called say_hello() twice, so it said hello two times! 🎉
That is the superpower of functions: write once, use many times.
Many Steps Inside
A recipe can have many steps inside. Watch this birthday recipe! 🎂
def birthday():
print("Happy Birthday!")
print("Make a wish!")
print("Blow the candles!")
birthday()Steps Stay Together
All the lines under def birthday(): are indented (pushed right with spaces).
That spacing tells Python "these steps belong to the recipe". 🧩
Functions Save Time
Good helpers do not repeat themselves. Functions help us be tidy coders! 🧹
Less typing, fewer mistakes, more fun. 😄
You Are a Chef Now
You learned what a function is: a saved recipe of steps with a name. 🍳
Next we will write our very own! Get ready! 🚀
Quick Check
Let us test your chef brain! 🧠
Great Job!
Woohoo! You now know what functions are. 🎉
Remember: a function = a reusable recipe. See you in the next lesson, chef! 👨🍳
Frequently asked questions
Is the “What Is a Function?” lesson free?
Yes — the full text of “What Is a Function?” is free to read here on the web, and the Coding for Kids course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Coding for Kids course, upgrade to CoddyKit PRO.
What will I learn in “What Is a Function?”?
A function is a reusable set of steps. You practise Coding for Kids with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Coding for Kids?
No prior experience is required. Coding for Kids on CoddyKit is structured for beginners through advanced learners; this is — lesson 1 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “What Is a Function?” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Coding for Kids lesson?
Yes. Every Coding for Kids lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- What Is a Function?
- Writing Your First Function
- Giving Functions Inputs
- Returning a Result