Scratch Game

Intermediate

60 mins

Teacher/Student led

+225 XP

What you need:
Chromebook/Laptop/PC or iPad/Tablet

Attack of the Dots

Get ready to create an exciting game in Scratch! You'll control a spinning disc to match colours with attacking dots. Learn to program the disc's movement, clone dots, and detect colours as you build this interactive project.

Learning Goals Learning Outcomes Curriculum Mapping Teacher Notes Lesson Files

Warning: Your screen size is quite small for viewing this. Rotate your device into landscape mode if you can.

1 Introduction
2 Remix the starter project
3 Make the disc spin
4 Clone the ball
5 Not too close!
6 Make them move
7 Detect the colour
8 Create purple and orange balls
9 Change the code for the purple and orange balls
10 Wrap up
Challenge
Quiz

1 - Introduction

Welcome to the 'Attack of the Dots' game project! In this exciting lesson, you will learn how to create a fun and interactive game using Scratch. You will control a colored disc in the middle of the screen, and your mission is to match the color of the disc with the colored dots that are attacking it. You will learn how to make the disc spin, clone the attacking dots, and detect the color of the dots. Let's get started and have some fun!

2 - Remix the starter project

We've created a starter project that has some custom sprites for this game.

Go to the starter project at the below link and click on the Remix button to create a copy of the project.

https://scratch.mit.edu/projects/281652790/editor/

Teacher Notes

https://scratch.mit.edu/projects/307852358/editor/ (beginners)

👇 Mark your steps as done as you complete them.

+10 XP

3 - Make the disc spin

In this game coloured balls will move towards the disc in the middle. You need to spin the wheel to match the colour of each ball as it hits the wheel. So we'll program the left and right arrow keys on our keyboard to spin the wheel in each direction.

Add the following code to the 'wheel' sprite:

when green flag clicked go to x[0] y [0] // place it in the center set size to [30]% // resize the wheel to 30% forever if < key (left arrow v) pressed? > then turn ccw (3) degrees // turn anti clockwise end if < key (right arrow v) pressed? > then turn cw (3) degrees // turn clockwise end end

Once you've added the code, click the green flag and test if your arrow keys spin the ball!

Scratch: Using a tablet or iPad? Tap here for different controls

If you're using a tablet or iPad without a physical keyboard, you won't be able to use keyboard keys like the arrow keys in your project. Instead, we'll add simple on-screen buttons (using sprites) that you can tap to do the same things. This keeps your project working great! Just follow these steps wherever the lesson talks about pressing a key.

First, add a new sprite for your button:

Click the "Choose a Sprite" button in the bottom right.
Pick a simple shape, like an arrow or a circle. Make it small and place it on the screen where it's easy to tap, like the bottom corner.

Now, program your button sprite to make things happen when you tap it. Here's how it works for different situations:

Example 1: If the lesson uses a key to trigger an action on a specific sprite (like making something move, turn, or jump)

Instead of code like this on your target sprite:

when [left arrow v] key pressed change x by (-10) // or any action

Or this:

if < key [left arrow v] pressed? > then change x by (-10) // or any action end

Add this code to your new button sprite:

when this sprite clicked broadcast [do action v]

Then, on your target sprite, add this to receive the message:

when I receive [do action v] change x by (-10) // or any action

Tap the button on the screen, and the action will happen, just like pressing the key! Use a unique broadcast name for each different action or key.

Example 2: If the lesson uses a key to change a variable (like adding to a score or setting a value)

Instead of code like this:

when [space v] key pressed change [score v] by (1)

Or this:

if < key [space v] pressed? > then change [score v] by (1) end

Add a new button sprite. Then, put this code on the button sprite:

when this sprite clicked change [score v] by (1)

(If the variable is "for this sprite only," make sure it's set to "for all sprites" so the button can change it.)

Tap the button, and the variable changes, no message needed since it's something shared!

+30 XP

4 - Clone the ball

In the game, the balls should appear every few seconds, in a random position and start moving towards the wheel.

Add the following code to the green ball called 'Sprite1':

when green flag clicked hide forever wait (pick random (4) to (8)) seconds // wait a random number of seconds create clone of (myself v) // create the clone end when I start as a clone go to (random position v) // start in a random position point towards (wheel v) // point in the direction of the wheel show

Click on the green flag and the green balls should start appearing in random places.

+35 XP

5 - Not too close!

We don't want the balls appearing too close to the wheel as it won't give us much time to react. So to prevent this add the following code to 'Sprite1' which detects where the ball is when it's cloned and deletes it if it's too close.

when I start as a clone go to (random position v) point towards (wheel v) show // add new code under here if < ( distance to (wheel v)) < (100) > then delete this clone end

Click on the green flag and check that no balls are being created too close to the wheel.

+15 XP

Unlock the Full Learning Experience

Get ready to embark on an incredible learning journey! Get access to this lesson and hundreds more in our Digital Skills Curriculum.

Get started

Copyright Notice
This lesson is copyright of Coding Ireland 2017 - 2025. Unauthorised use, copying or distribution is not allowed.

Scratch is developed by the Lifelong Kindergarten Group at the MIT Media Lab. It is available for free at https://scratch.mit.edu

Attack of the Dots

Teacher Class Feed

1 - Introduction

Send your work to your teacher

2 - Remix the starter project

Send your work to your teacher

3 - Make the disc spin

Send your work to your teacher

4 - Clone the ball

Send your work to your teacher

5 - Not too close!

Send your work to your teacher

Unlock the Full Learning Experience