Adding and Subtracting
Do simple math with plus and minus.
Adding and Subtracting is a free Javascript 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 Javascript for Kids learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Math Magic!
Hello, math wizard! 🧙 Today you will make the computer add and subtract! ➕➖
The Plus Sign
The + sign means add. 🔢
It puts numbers together to make a bigger number!
Add Two Numbers
Run this to add 2 and 3! ▶️
console.log(2 + 3)Add More Numbers
You can add lots of numbers at once! Run this. ➕
console.log(1 + 2 + 3 + 4)The Minus Sign
The - sign means subtract, which means take away. ➖
It makes numbers smaller!
Subtract Numbers
Run this to take 4 away from 10! 🍪
console.log(10 - 4)Cookies Story
You have 8 cookies and eat 3. How many are left? Run it! 🍪😋
console.log(8 - 3)Mix Plus and Minus
You can add AND subtract in one line! Run this. 🔀
console.log(10 + 5 - 3)Add Your Treasure
Count your coins! You find 5, then 7 more. 🪙 Run this.
console.log(5 + 7)Take Away Steps
You walk 20 steps, then back up 6. Run this! 👣
console.log(20 - 6)You Are a Calculator!
The computer can add and subtract super fast! ⚡
You just told it exactly what to do. Great work!
Quick Check
Math quiz! 🧮
Adding Ace!
Yay! 🎉 You learned to add with + and subtract with -.
You are a math wizard in training! 🧙✨
Frequently asked questions
Is the “Adding and Subtracting” lesson free?
Yes — the full text of “Adding and Subtracting” is free to read here on the web, and the Javascript 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 Javascript for Kids course, upgrade to CoddyKit PRO.
What will I learn in “Adding and Subtracting”?
Do simple math with plus and minus. You practise Javascript 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 Javascript for Kids?
No prior experience is required. Javascript 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 “Adding and Subtracting” 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 Javascript for Kids lesson?
Yes. Every Javascript 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
- Adding and Subtracting
- Multiplying and Dividing
- The Remainder Trick
- Math with Variables