Introduction & Basic Movement — Scratch L1 Topic 1.1

Learnt30 min · what Scratch is, the editor, your first motion blocks
Basic25 min · you build it yourself
Challenge 1–327 min · a square, an S, an endless circle
Extrabonus · write your initial in the air

WHAT IT SHOULD LOOK LIKE

What we are making today. The cat walks a square and comes back to the corner it started from.

today’s project

Today’s Topic 3 min

What is Scratch, and why learn it?
Create your own Scratch account
The Scratch editor — every part of the screen
Your first motion blocks: move (10) steps, turn cw (15) degrees, go to x: (0) y: (0)
Make the cat move in a square

Learning outcome

By the end of this lesson you will be able to:

Log in to your own Scratch account and click Create to open a new project.
Point to the Stage, the Sprite panel, the Blocks Panel and the Script Area, and say what each one is for.
Build a stack that sets the cat’s starting position and direction, then moves and turns it — and run it with the green flag.

Learnt — what Scratch is, and your first blocks 30 min

What is Scratch?

In Scratch you build programs by snapping blocks together, like LEGO. You do not type code. You drag a coloured brick into place and it works. With those bricks you can make animations, games and stories.

Why learn it? Scratch is free. It runs in any web browser. The sprites and backdrops are free too. And you can open anybody’s project and look inside to see how they made it.

Get your own Scratch account

Go to scratch.mit.edu. Click Join Scratch. You need your own account, because every lesson ends with you sending a project link to your teacher.

Step	What you type	Watch out
1. Username	A nickname you will remember	Do not use your real full name
2. Password	Something you can spell twice	Write it on paper and keep it in your desk
3. Country	the world	—
4. Birth month and year	Your own	—
5. Gender	Your own	“Prefer not to say” is a real option
6. Email	Yours, or a parent’s	You must open the email and verify

Now sign in and click Create. A new empty project opens. The cat is already standing on the Stage.

The Scratch editor

This is the whole screen. Find each number on your own screen before you read what it does.

#	Part	What it is for
1	Blocks Panel	Every block, sorted into nine coloured categories.
2	Script Area	The big empty space you drag blocks into. Your program lives here.
3	Stage	The white box everyone watches. Sprites live here and cannot walk off it.
4	Green flag and red stop	The green flag runs your program. The red octagon stops everything.
5	View modes	Small stage, big stage, or full screen with no code showing.
6	Sprite panel	Every character in the project: name, position, size and direction.
7	Add a sprite or a backdrop	The cat button adds a character. The picture button adds a background. A backdrop never moves — it sits behind everything.

The three view modes

Button 5 changes how big the Stage is. Try all three.

The Scratch editor with the small stage selected: a wide Script Area and a narrow Stage — Small stage — more room for blocks.

The Scratch editor with the large stage selected — Big stage — the normal one.

The Scratch stage filling the whole screen, with only a green flag and a stop sign above it — Full screen — no code at all. This is how other people play your project.

The sprite’s own settings

Click your cat in the Sprite panel, under the Stage. This is what you see. You can change five things here with no blocks at all.

The Sprite panel. The cat is selected, so its tile is blue. The arrows point at the five settings in the list below.

Name — rename it. Do this as soon as you have two sprites, so your code says Cat and Dog, not Sprite1 and Sprite2.
x and y — where it is standing. Both boxes show 0, so this cat is in the middle.
Show / hide — the two eye buttons. The open eye is on, so you can see the cat. The crossed eye hides it.
Size — a percentage. 100 is normal, 50 is half, 200 is double.
Direction — which way it faces. 90 is right.

The direction dial

Click the Direction box. A dial pops open.

The Scratch direction dial open over the Stage, with the three rotation style buttons underneath it — The direction dial, and the three rotation styles underneath it.

Click the Direction box to open the dial.
Drag the purple arrow round to turn the cat.
The three small buttons are the rotation style: turn all the way round, flip left and right only, or never turn at all. You use the middle one in Lesson 2, and the first one is why your cat tips over today.

Adding a second character, and a background

The two round buttons at the bottom right are how you add things. Hover over one and more buttons slide out: upload your own, get a surprise one, paint your own, or search the library.

Choose a Sprite — a new character. You use this in Lesson 2.

The Choose a Backdrop button at the bottom right of the Stage column, with its four options open — Choose a Backdrop — a background behind everything.

The Stage is a grid

Every place on the Stage has two numbers, (x, y). The middle is (0, 0).

Move right and x gets bigger. Move left and x gets smaller.
Move up and y gets bigger. Move down and y gets smaller.

Drag the cat around with your mouse. Watch the x and y boxes in the Sprite panel change.

The Stage is 480 wide and 360 tall. x runs from −240 on the left to +240 on the right. y runs from −180 at the bottom to +180 at the top. The cat starts in the middle, at (0, 0).

Nine colours of block

Every block has a colour, and the colour tells you which drawer it came from. Find these nine down the left of the Blocks Panel.

Category	What it controls
Motion	Moving and turning the sprite
Looks	Costumes, speech bubbles, size, show and hide
Sound	Playing and changing sounds
Events	What sets a script running
Control	Waiting, repeating, deciding
Sensing	Noticing touches, keys and the mouse
Operators	Sums, comparisons, random numbers
Variables	Remembering a number or some words
My Blocks	Blocks you invent yourself

Today you only need two of them: Events to start the program, and Motion to move the cat.

Your first two blocks

Open Events. Drag when flag clicked into the Script Area.
Open Motion. Drag move (10) steps underneath it.
Watch for the faint white line before you let go. That is Scratch saying the two blocks will snap together.
Click the number and change it to 100. Then click the green flag.

The first block has a rounded top. That shape means “nothing can go above me”. We call it a hat block. Every script starts with one.


when flag clicked
move (100) steps

Click the green flag and the cat jumps 100 pixels to the right. Click again and it jumps another 100.

WHAT IT SHOULD LOOK LIKE

Two blocks, one click. The cat starts at the left so 100 steps reads as a real journey.

before the click

after the click

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

Press the green flag. One click, one jump of 100 steps.

Change the number, change the jump

The white circle in the block is a box. You can type in it.

Click the white circle inside move (100) steps.
Type a new number. Try 10. Then try 200.
Click the green flag.
Watch how far the cat goes.

move (10) steps

a tiny creep

move (100) steps

a normal walk

move (200) steps

a big leap

One step is one pixel. The Stage is 480 pixels wide. So 100 steps is about a fifth of the way across.

WHAT IT SHOULD LOOK LIKE

Three cats. They all start in the same place. Only the number in the block is different.

before the click

after one click

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

Three cats, three numbers. Press the green flag once. They all move at the same time, so you can see the difference.

Repeat — one jump becomes a walk

One big jump is not a walk. The cat is just somewhere else. To make it travel, cut the journey into small pieces.

Open Control. Drag repeat (10) into the Script Area.
Drop move (10) steps inside the mouth of the repeat block.
Click the green flag and watch the cat walk.


when flag clicked
repeat (10)
  move (10) steps
end

Ten repeats of 10 steps is still 100 steps. But now you can watch it happen. One trip round a repeat takes about 0.03 seconds.

WHAT IT SHOULD LOOK LIKE

Ten steps of 10 land in exactly the same spot as one jump of 100 — but this time you watch the cat walk there.

green flag

ten repeats later

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

The same 100 steps as the embed above, taken in ten pieces. It glides instead of jumping. (This demo starts at the left every time, using a block you meet in a moment.)

Faster, or further?

Two numbers, two different jobs. It is easy to mix them up:

A bigger number in the repeat block means further. More pieces of journey.
A bigger number in the move block means faster. Bigger pieces, same number of them.

Try both now. Change one number at a time. Say out loud what you think will happen first.

Always start from the same place

Click the flag three times. The cat drifts off the edge. That is because it starts from wherever it stopped last time.

Fix it by telling the cat where to begin. Drag go to x: (0) y: (0) straight under the hat block.


when flag clicked
go to x: (0) y: (0)
repeat (10)
  move (10) steps
end

Now every run starts in the middle. The cat does the same thing every time.

Turning

turn cw (15) degrees spins the cat clockwise (to the right). turn ccw (15) degrees spins it anticlockwise (to the left).

Turning never moves the cat. It only changes which way the cat points. That is what decides where the next move block sends it.

WHAT IT SHOULD LOOK LIKE

Turning changes the direction the cat faces — it does not move the cat anywhere.

facing right

after nine small turns of 10 degrees

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

Nine turns of 10 degrees. Watch the cat's feet. It swings round to face downwards without moving one pixel.

One turn cw (90) degrees snaps round instantly. To watch the turn, break it up, the same way you broke up the walk:


when flag clicked
repeat (9)
  turn cw (10) degrees
end

Nine small turns of 10 degrees add up to one quarter-turn. Now you can see it.

Setting the starting direction

Direction is a number too:

90 is right, 0 is up
−90 is left, 180 is down

A sprite keeps the direction you left it in. So a script that turns should also set its direction at the start, with point in direction (90 v). Same idea as setting the position.

Basic — now build it yourself 25 min

Your teacher showed you all of that. Now you do it, on your own computer.

Your target: a cat that

always starts in the middle, facing right,
walks 200 steps,
then turns a quarter-turn.

WHAT IT SHOULD LOOK LIKE

Your build: the cat always begins at the centre facing right, walks 200 steps, then turns a quarter-turn.

green flag

after the walk, and the turn

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

What you are aiming at. Build it yourself first, then press this to check. Press it twice — doing the same thing twice is half the point.

Step 1 — open a fresh project

Step 2 — the hat block

Events → drag when flag clicked into the Script Area. Click the flag. Nothing happens, and that is correct. The hat block is waiting for something to do.

Step 3 — set the starting position

Motion → snap go to x: (0) y: (0) under the hat. Now drag the cat anywhere with your mouse and click the flag. It jumps back to the middle.

Step 4 — set the starting direction

Snap point in direction (90 v) underneath. Now spin the cat by hand with the direction dial in the Sprite panel. Click the flag again. It straightens up.

Step 5 — walk

Snap move (200) steps on the end. Click the flag. The cat crosses to the right side of the Stage in one jump.

Step 6 — make the walk visible

One jump is not a walk. Put the move block inside repeat (20) and change it to move (10) steps. Twenty tens is still 200. But now you watch the cat get there.

Step 7 — turn at the end

Snap turn cw (90) degrees after the repeat block. Outside it, not inside. Click the flag. The cat walks across, then faces downwards.

Step 8 — check your work against this


when flag clicked
go to x: (0) y: (0)
point in direction (90 v)
repeat (20)
  move (10) steps
end
turn cw (90) degrees

Six blocks. Your Script Area should look exactly like this. Click the flag five times. It must do the same thing all five times.

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

The finished Basic build. Press the flag more than once. The two setup blocks are what make it do the same thing every time.

It does something different every time I click — why?

You are missing one of the two setup blocks. Without go to x: (0) y: (0) the cat starts from wherever it stopped last. Without point in direction (90 v) it starts facing wherever it was last turned. Both go directly under the hat block, before the repeat.

CHALLENGE 1 · T1.1-M1🪙 30 Adcoins8 min

Move the cat in a big square

Send the cat round a square and bring it home.

Every side is 200 steps.
Every corner is a 90 degree turn.
It starts in the same place every run.

WHAT IT SHOULD LOOK LIKE

Challenge 1 — the cat walks a big square. Each side is 200 steps. It finishes on the corner it started from.

the route

one lap later

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

The finished square. Press the flag and follow one lap with your finger. Four sides of 200 steps, four corners, home again. The cat rolls over at each corner. That is normal, and Lesson 3 shows you how to stop it.

Done when: you click the green flag. The cat walks four sides of 200 steps, turns four times, and stops on the corner it started from, facing the same way. Click again and it does the same thing.

Teacher reveal — the square


when flag clicked
go to x: (-100) y: (100)
point in direction (90 v)
repeat (4)
  repeat (20)
    move (10) steps
  end
  turn cw (90) degrees
end

One side and one corner, done four times. That is the idea the challenge is looking for. 360 ÷ 4 = 90, so a 90 degree turn at each corner brings the cat back to direction 90.

20 × 10 = 200, so the inner repeat (20) walks one full side. It is also why the embed is watchable. The short way — repeat (4) holding move (200) steps and turn cw (90) degrees — draws the same square in about four frames, so nobody sees the cat move. Both are correct. Accept either, then ask the pupil to make theirs visible.

CHALLENGE 2 · T1.1-M2🪙 50 Adcoins9 min

Can you make an “S” shape?

This is a block S. No curves. Straight lines and 90 degree corners only — the same two ideas as the square.

Five straight lines: three long ones and two short ones.
Four corners, all 90 degrees.
The first two corners turn left. The last two turn right.

That swap in the middle is what makes an S. Without it you get a spiral.

WHAT IT SHOULD LOOK LIKE

Challenge 2 — a block letter S. Straight lines and corners only. No curves.

the route

at the end of the S

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

The finished S. Watch the corners. The first two turn one way, the last two turn the other way.

Done when: the cat walks an S from the top of the Stage to the bottom. Every line is straight. Every corner is 90 degrees. The cat finishes facing the way it started.

Teacher reveal — the S

What your pupil builds. Five moves and four turns, in this order:


when flag clicked
go to x: (100) y: (120)
point in direction (-90 v)
move (200) steps
turn ccw (90) degrees
move (120) steps
turn ccw (90) degrees
move (200) steps
turn cw (90) degrees
move (120) steps
turn cw (90) degrees
move (200) steps

The cat starts at the top right facing left, the way a child writes an S. Two left turns then two right turns cancel out, so it finishes facing left again. A mirrored S — start at the bottom left facing right, turn right twice then left twice — is equally correct.

What the embed above runs. The same route, with every stroke broken into small steps so the class can watch it happen. Five move (200) steps blocks draw the letter in five frames and nobody sees a thing.


when flag clicked
go to x: (100) y: (120)
point in direction (-90 v)
repeat (20)
  move (10) steps
end
turn ccw (90) degrees
repeat (12)
  move (10) steps
end
turn ccw (90) degrees
repeat (20)
  move (10) steps
end
turn cw (90) degrees
repeat (12)
  move (10) steps
end
turn cw (90) degrees
repeat (20)
  move (10) steps
end

CHALLENGE 3 · T1.1-M3🪙 70 Adcoins10 min

How do you make the cat keep moving in a circle?

Not one lap. Endless laps.

A circle is a lot of tiny moves with a tiny turn after each one. You already did this in the Learnt section, when nine small turns added up to one quarter-turn.

The cat must still be going round when you get bored of watching. Only the red stop sign stops it.

WHAT IT SHOULD LOOK LIKE

Challenge 3 — the cat goes round the same circle again and again. Only the red stop sign stops it.

the route

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

The endless circle. It keeps going until you press the red stop sign. Your version must do the same.

Done when: one click of the green flag sends the cat round a circle again and again with no gap and no stutter between laps, and the only thing that stops it is the red stop sign.

Teacher reveal — the endless circle


when flag clicked
go to x: (0) y: (115)
point in direction (90 v)
forever
  move (10) steps
  turn cw (5) degrees
end

forever is the block this challenge exists to make pupils want. A repeat (72) also draws one lap, because 72 × 5 = 360. But it stops, and the brief says it must not. Look at the shape of forever: there is no bump underneath, because nothing can run after it.

The two numbers decide how big the circle is. A move of 10 with a turn of 5 gives a circle about 115 wide from the middle — the one drawn above. Bigger moves make a bigger circle; bigger turns make a smaller one. Any pair that keeps the cat on the Stage is correct.

EXTRA MISSION · T1.1-MX🪙 100 Adcoinsbonus

Write your initial in the air

You can make the cat walk straight lines, sharp corners and round curves. That is everything you need to walk the shape of a letter.

Make the cat walk the first letter of your own name, as a capital. Make it big enough to fill most of the Stage. There is no pen and no drawing — just the cat’s route. Somebody watching over your shoulder should be able to say the letter before the cat finishes.

WHAT IT SHOULD LOOK LIKE

Extra Mission — the cat walks the shape of a capital letter. This one is an A; yours is your own initial.

the route for an A

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

One letter done for you — an A. Watch the moment between the second leg and the cross-bar. The cat does not walk there. It jumps. Yours will need that too.

Summary 5 min

Scratch is free block coding. You build programs by snapping bricks together.
You have your own verified account. You hand work in by sharing a project link.
The Stage is a grid. The middle is (0, 0). x runs −240 to +240. y runs −180 to +180.
Every script starts with a hat block. when flag clicked is the one you will use most.
Motion blocks move and turn the sprite.
Control blocks like repeat (10) and forever do the same thing over and over.
Set the starting position and the starting direction. If you do not, your program does something different on its second run.

Sprite: A character on the Stage that follows the blocks you give it.
Hat block: A rounded-top block that starts a script — nothing can sit above it.
Step: One pixel of travel, in whichever direction the sprite is currently facing.
Direction: Which way a sprite faces: 90 is right, 0 up, −90 left, 180 down.

Hand in

Save your project. Click Share. Send the link to your teacher. Missions you finish at home count too. Bring the link to the next class and claim your Adcoins.

Learnt30 min · what Scratch is, the editor, your first motion blocks
Basic25 min · you build it yourself
Challenge 1–327 min · a square, an S, an endless circle
Extrabonus · write your initial in the air

WHAT IT SHOULD LOOK LIKE

What we are making today. The cat walks a square and comes back to the corner it started from.

today’s project

Today’s Topic 3 min

What is Scratch, and why learn it?
Create your own Scratch account
The Scratch editor — every part of the screen
Your first motion blocks: move (10) steps, turn cw (15) degrees, go to x: (0) y: (0)
Make the cat move in a square

Learning outcome

By the end of this lesson you will be able to:

Log in to your own Scratch account and click Create to open a new project.
Point to the Stage, the Sprite panel, the Blocks Panel and the Script Area, and say what each one is for.
Build a stack that sets the cat’s starting position and direction, then moves and turns it — and run it with the green flag.

Learnt — what Scratch is, and your first blocks 30 min

What is Scratch?

Why learn it? Scratch is free. It runs in any web browser. The sprites and backdrops are free too. And you can open anybody’s project and look inside to see how they made it.

Get your own Scratch account

Go to scratch.mit.edu. Click Join Scratch. You need your own account, because every lesson ends with you sending a project link to your teacher.

Step	What you type	Watch out
1. Username	A nickname you will remember	Do not use your real full name
2. Password	Something you can spell twice	Write it on paper and keep it in your desk
3. Country	the world	—
4. Birth month and year	Your own	—
5. Gender	Your own	“Prefer not to say” is a real option
6. Email	Yours, or a parent’s	You must open the email and verify

Now sign in and click Create. A new empty project opens. The cat is already standing on the Stage.

The Scratch editor

This is the whole screen. Find each number on your own screen before you read what it does.

#	Part	What it is for
1	Blocks Panel	Every block, sorted into nine coloured categories.
2	Script Area	The big empty space you drag blocks into. Your program lives here.
3	Stage	The white box everyone watches. Sprites live here and cannot walk off it.
4	Green flag and red stop	The green flag runs your program. The red octagon stops everything.
5	View modes	Small stage, big stage, or full screen with no code showing.
6	Sprite panel	Every character in the project: name, position, size and direction.
7	Add a sprite or a backdrop	The cat button adds a character. The picture button adds a background. A backdrop never moves — it sits behind everything.

The three view modes

Button 5 changes how big the Stage is. Try all three.

The sprite’s own settings

Click your cat in the Sprite panel, under the Stage. This is what you see. You can change five things here with no blocks at all.

The Sprite panel. The cat is selected, so its tile is blue. The arrows point at the five settings in the list below.

Name — rename it. Do this as soon as you have two sprites, so your code says Cat and Dog, not Sprite1 and Sprite2.
x and y — where it is standing. Both boxes show 0, so this cat is in the middle.
Show / hide — the two eye buttons. The open eye is on, so you can see the cat. The crossed eye hides it.
Size — a percentage. 100 is normal, 50 is half, 200 is double.
Direction — which way it faces. 90 is right.

The direction dial

Click the Direction box. A dial pops open.

Click the Direction box to open the dial.
Drag the purple arrow round to turn the cat.
The three small buttons are the rotation style: turn all the way round, flip left and right only, or never turn at all. You use the middle one in Lesson 2, and the first one is why your cat tips over today.

Adding a second character, and a background

The two round buttons at the bottom right are how you add things. Hover over one and more buttons slide out: upload your own, get a surprise one, paint your own, or search the library.

Choose a Sprite — a new character. You use this in Lesson 2.

The Stage is a grid

Every place on the Stage has two numbers, (x, y). The middle is (0, 0).

Move right and x gets bigger. Move left and x gets smaller.
Move up and y gets bigger. Move down and y gets smaller.

Drag the cat around with your mouse. Watch the x and y boxes in the Sprite panel change.

The Stage is 480 wide and 360 tall. x runs from −240 on the left to +240 on the right. y runs from −180 at the bottom to +180 at the top. The cat starts in the middle, at (0, 0).

Nine colours of block

Every block has a colour, and the colour tells you which drawer it came from. Find these nine down the left of the Blocks Panel.

Category	What it controls
Motion	Moving and turning the sprite
Looks	Costumes, speech bubbles, size, show and hide
Sound	Playing and changing sounds
Events	What sets a script running
Control	Waiting, repeating, deciding
Sensing	Noticing touches, keys and the mouse
Operators	Sums, comparisons, random numbers
Variables	Remembering a number or some words
My Blocks	Blocks you invent yourself

Today you only need two of them: Events to start the program, and Motion to move the cat.

Your first two blocks

Open Events. Drag when flag clicked into the Script Area.
Open Motion. Drag move (10) steps underneath it.
Watch for the faint white line before you let go. That is Scratch saying the two blocks will snap together.
Click the number and change it to 100. Then click the green flag.

The first block has a rounded top. That shape means “nothing can go above me”. We call it a hat block. Every script starts with one.


when flag clicked
move (100) steps

Click the green flag and the cat jumps 100 pixels to the right. Click again and it jumps another 100.

WHAT IT SHOULD LOOK LIKE

Two blocks, one click. The cat starts at the left so 100 steps reads as a real journey.

before the click

after the click

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

Press the green flag. One click, one jump of 100 steps.

Change the number, change the jump

The white circle in the block is a box. You can type in it.

Click the white circle inside move (100) steps.
Type a new number. Try 10. Then try 200.
Click the green flag.
Watch how far the cat goes.

move (10) steps

a tiny creep

move (100) steps

a normal walk

move (200) steps

a big leap

One step is one pixel. The Stage is 480 pixels wide. So 100 steps is about a fifth of the way across.

WHAT IT SHOULD LOOK LIKE

Three cats. They all start in the same place. Only the number in the block is different.

before the click

after one click

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

Three cats, three numbers. Press the green flag once. They all move at the same time, so you can see the difference.

Repeat — one jump becomes a walk

One big jump is not a walk. The cat is just somewhere else. To make it travel, cut the journey into small pieces.

Open Control. Drag repeat (10) into the Script Area.
Drop move (10) steps inside the mouth of the repeat block.
Click the green flag and watch the cat walk.


when flag clicked
repeat (10)
  move (10) steps
end

Ten repeats of 10 steps is still 100 steps. But now you can watch it happen. One trip round a repeat takes about 0.03 seconds.

WHAT IT SHOULD LOOK LIKE

Ten steps of 10 land in exactly the same spot as one jump of 100 — but this time you watch the cat walk there.

green flag

ten repeats later

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

The same 100 steps as the embed above, taken in ten pieces. It glides instead of jumping. (This demo starts at the left every time, using a block you meet in a moment.)

Faster, or further?

Two numbers, two different jobs. It is easy to mix them up:

A bigger number in the repeat block means further. More pieces of journey.
A bigger number in the move block means faster. Bigger pieces, same number of them.

Try both now. Change one number at a time. Say out loud what you think will happen first.

Always start from the same place

Click the flag three times. The cat drifts off the edge. That is because it starts from wherever it stopped last time.

Fix it by telling the cat where to begin. Drag go to x: (0) y: (0) straight under the hat block.


when flag clicked
go to x: (0) y: (0)
repeat (10)
  move (10) steps
end

Now every run starts in the middle. The cat does the same thing every time.

Turning

turn cw (15) degrees spins the cat clockwise (to the right). turn ccw (15) degrees spins it anticlockwise (to the left).

Turning never moves the cat. It only changes which way the cat points. That is what decides where the next move block sends it.

WHAT IT SHOULD LOOK LIKE

Turning changes the direction the cat faces — it does not move the cat anywhere.

facing right

after nine small turns of 10 degrees

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

Nine turns of 10 degrees. Watch the cat's feet. It swings round to face downwards without moving one pixel.

One turn cw (90) degrees snaps round instantly. To watch the turn, break it up, the same way you broke up the walk:


when flag clicked
repeat (9)
  turn cw (10) degrees
end

Nine small turns of 10 degrees add up to one quarter-turn. Now you can see it.

Setting the starting direction

Direction is a number too:

90 is right, 0 is up
−90 is left, 180 is down

A sprite keeps the direction you left it in. So a script that turns should also set its direction at the start, with point in direction (90 v). Same idea as setting the position.

Basic — now build it yourself 25 min

Your teacher showed you all of that. Now you do it, on your own computer.

Your target: a cat that

always starts in the middle, facing right,
walks 200 steps,
then turns a quarter-turn.

WHAT IT SHOULD LOOK LIKE

Your build: the cat always begins at the centre facing right, walks 200 steps, then turns a quarter-turn.

green flag

after the walk, and the turn

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

What you are aiming at. Build it yourself first, then press this to check. Press it twice — doing the same thing twice is half the point.

Step 1 — open a fresh project

Step 2 — the hat block

Events → drag when flag clicked into the Script Area. Click the flag. Nothing happens, and that is correct. The hat block is waiting for something to do.

Step 3 — set the starting position

Motion → snap go to x: (0) y: (0) under the hat. Now drag the cat anywhere with your mouse and click the flag. It jumps back to the middle.

Step 4 — set the starting direction

Snap point in direction (90 v) underneath. Now spin the cat by hand with the direction dial in the Sprite panel. Click the flag again. It straightens up.

Step 5 — walk

Snap move (200) steps on the end. Click the flag. The cat crosses to the right side of the Stage in one jump.

Step 6 — make the walk visible

One jump is not a walk. Put the move block inside repeat (20) and change it to move (10) steps. Twenty tens is still 200. But now you watch the cat get there.

Step 7 — turn at the end

Snap turn cw (90) degrees after the repeat block. Outside it, not inside. Click the flag. The cat walks across, then faces downwards.

Step 8 — check your work against this


when flag clicked
go to x: (0) y: (0)
point in direction (90 v)
repeat (20)
  move (10) steps
end
turn cw (90) degrees

Six blocks. Your Script Area should look exactly like this. Click the flag five times. It must do the same thing all five times.

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

The finished Basic build. Press the flag more than once. The two setup blocks are what make it do the same thing every time.

It does something different every time I click — why?

CHALLENGE 1 · T1.1-M1🪙 30 Adcoins8 min

Move the cat in a big square

Send the cat round a square and bring it home.

Every side is 200 steps.
Every corner is a 90 degree turn.
It starts in the same place every run.

WHAT IT SHOULD LOOK LIKE

Challenge 1 — the cat walks a big square. Each side is 200 steps. It finishes on the corner it started from.

the route

one lap later

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

Done when: you click the green flag. The cat walks four sides of 200 steps, turns four times, and stops on the corner it started from, facing the same way. Click again and it does the same thing.

Teacher reveal — the square


when flag clicked
go to x: (-100) y: (100)
point in direction (90 v)
repeat (4)
  repeat (20)
    move (10) steps
  end
  turn cw (90) degrees
end

One side and one corner, done four times. That is the idea the challenge is looking for. 360 ÷ 4 = 90, so a 90 degree turn at each corner brings the cat back to direction 90.

CHALLENGE 2 · T1.1-M2🪙 50 Adcoins9 min

Can you make an “S” shape?

This is a block S. No curves. Straight lines and 90 degree corners only — the same two ideas as the square.

Five straight lines: three long ones and two short ones.
Four corners, all 90 degrees.
The first two corners turn left. The last two turn right.

That swap in the middle is what makes an S. Without it you get a spiral.

WHAT IT SHOULD LOOK LIKE

Challenge 2 — a block letter S. Straight lines and corners only. No curves.

the route

at the end of the S

panels run left to right

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

The finished S. Watch the corners. The first two turn one way, the last two turn the other way.

Done when: the cat walks an S from the top of the Stage to the bottom. Every line is straight. Every corner is 90 degrees. The cat finishes facing the way it started.

Teacher reveal — the S

What your pupil builds. Five moves and four turns, in this order:


when flag clicked
go to x: (100) y: (120)
point in direction (-90 v)
move (200) steps
turn ccw (90) degrees
move (120) steps
turn ccw (90) degrees
move (200) steps
turn cw (90) degrees
move (120) steps
turn cw (90) degrees
move (200) steps


when flag clicked
go to x: (100) y: (120)
point in direction (-90 v)
repeat (20)
  move (10) steps
end
turn ccw (90) degrees
repeat (12)
  move (10) steps
end
turn ccw (90) degrees
repeat (20)
  move (10) steps
end
turn cw (90) degrees
repeat (12)
  move (10) steps
end
turn cw (90) degrees
repeat (20)
  move (10) steps
end

CHALLENGE 3 · T1.1-M3🪙 70 Adcoins10 min

How do you make the cat keep moving in a circle?

Not one lap. Endless laps.

A circle is a lot of tiny moves with a tiny turn after each one. You already did this in the Learnt section, when nine small turns added up to one quarter-turn.

The cat must still be going round when you get bored of watching. Only the red stop sign stops it.

WHAT IT SHOULD LOOK LIKE

Challenge 3 — the cat goes round the same circle again and again. Only the red stop sign stops it.

the route

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

The endless circle. It keeps going until you press the red stop sign. Your version must do the same.

Done when: one click of the green flag sends the cat round a circle again and again with no gap and no stutter between laps, and the only thing that stops it is the red stop sign.

Teacher reveal — the endless circle


when flag clicked
go to x: (0) y: (115)
point in direction (90 v)
forever
  move (10) steps
  turn cw (5) degrees
end

EXTRA MISSION · T1.1-MX🪙 100 Adcoinsbonus

Write your initial in the air

You can make the cat walk straight lines, sharp corners and round curves. That is everything you need to walk the shape of a letter.

WHAT IT SHOULD LOOK LIKE

Extra Mission — the cat walks the shape of a capital letter. This one is an A; yours is your own initial.

the route for an A

Runs here in the page. Nothing to install.

How to use this: Click the green flag to start it. Nothing else to press — watch it through, then use ↺ Reset to run it again.

One letter done for you — an A. Watch the moment between the second leg and the cross-bar. The cat does not walk there. It jumps. Yours will need that too.

Summary 5 min

Scratch is free block coding. You build programs by snapping bricks together.
You have your own verified account. You hand work in by sharing a project link.
The Stage is a grid. The middle is (0, 0). x runs −240 to +240. y runs −180 to +180.
Every script starts with a hat block. when flag clicked is the one you will use most.
Motion blocks move and turn the sprite.
Control blocks like repeat (10) and forever do the same thing over and over.
Set the starting position and the starting direction. If you do not, your program does something different on its second run.

Sprite: A character on the Stage that follows the blocks you give it.
Hat block: A rounded-top block that starts a script — nothing can sit above it.
Step: One pixel of travel, in whichever direction the sprite is currently facing.
Direction: Which way a sprite faces: 90 is right, 0 up, −90 left, 180 down.

Hand in

Save your project. Click Share. Send the link to your teacher. Missions you finish at home count too. Bring the link to the next class and claim your Adcoins.