Getting started with Scratch

What is Scratch?

Scratch is a free tool, made by MIT, that lets you build games, animations and stories by snapping colourful blocks together instead of typing code. Each block is an instruction — "move 10 steps," "say Hello," "when the green flag is clicked" — and you drag them into a stack to make a program. It's the way millions of children around the world start coding, because you can make something fun in minutes.

Open Scratch (free, nothing to install)

1. Open a web browser and go to scratch.mit.edu.
2. Click Create at the top. The Scratch editor opens.

That's it — no download, no cost. It works on a computer or a tablet (a computer is easier).

About accounts: you can build and play projects without signing in. To *save* your projects, you need a free Scratch account, and for children under 13 that account is made with a parent's email and permission. You don't need an account for this lesson, so a grown-up can sort that out later if you want to save your work.

A quick tour of the screen

• Blocks palette (left): all the blocks, sorted into coloured groups — blue Motion, purple Looks, yellow Events, orange Control, and more.
• Code area (middle): where you drag blocks and snap them together.
• Stage (top right): where your project runs. The cat starts here.
• Sprites (below the stage): the characters in your project. You start with one — the Scratch cat.

Your first program

Let's make the cat move and talk.

1. Click the Events group (yellow) and drag when green flag clicked into the code area.
2. Click Motion (blue) and drag move 10 steps so it snaps *under* the yellow block.
3. Click Looks (purple) and drag say Hello! for 2 seconds under that.
4. Click the green flag above the stage.

The cat moves a little and says "Hello!" You just wrote a program: three blocks, run in order, top to bottom.

Make it yours

• Change 10 steps to 100 and click the flag again. Bigger jump!
• Change the words in the say block to your name.
• Add another move block. What happens?

The way to learn Scratch is exactly this: change a block, click the flag, see what happens. You can't break anything.

Try it

• Make the cat move, then say two different things one after the other.
• Make it move a big number of steps, then a negative number like -100. Which way does it go?
• Find the red stop button (next to the green flag) and use it.

For the grown-up

Everything is free at scratch.mit.edu with nothing to install. Projects run without an account; saving needs one, made with your email for under-13s. Sit with younger children for this first lesson; after that most can explore on their own.