Start a new Scratch project, and delete the cat sprite so that your project is empty. You can find the online Scratch editor at jumpto.cc/scratch-new.

For this project, you should have a ‘Project Resources’ folder, containing the controller image you can use. Make sure that you can find this folder, and ask your club leader if you can’t find it.

From this ‘Project Resources’ folder, import ‘controller.png’ as a new sprite. If you don’t have this image you can draw it yourself! You should also make the stage black. Here’s how your stage should look:

You can move your controller really easily, by turning it left or right when the arrows are pressed:

    when flag clicked
    forever
        if <key [left arrow v] pressed?> then
            turn left (2) degrees
        end
        if <key [right arrow v] pressed?> then
            turn right (2) degrees
        end
    end

Test out your controller – it should spin left and right.

Although this code works, it would be much better if the controller sped up and slowed down gradually. To do this, delete the code you just created for your controller, and create a new variable called controller speed.

Add this code to your controller, to make it repeatedly use the controller speed to move:

    when flag clicked
    set [controller speed v] to [0]
    forever
        turn right (controller speed) degrees
    end

At the moment, this code won’t move the controller, as the speed has been set to 0! Create a separate script in your controller that increases the speed when the right arrow is pressed.

    when flag clicked
    forever
        if <key [right arrow v] pressed?> then
            change [controller speed v] by (0.2)
        else

        end
    end

Have you noticed that there’s a gap in the code above? You will need to add some code to slow down the controller if the right arrow key isn’t pressed. However, you only want to slow down the controller until the speed gets back down to 0, otherwise it’ll start spinning backwards.

Here’s the code you should add:

if <(controller speed) > [0.1]> then
    change [controller speed v] by (-0.2)
end

Here’s how your controller code should look:

Test your project again. If you hold down the right arrow key your controller should speed up. Let go of the key and your controller should gradually slow down.

Create a new sprite called ‘red’. This sprite should be a small red dot.

Add this script to your ‘red’ dot sprite, to create a new dot clone every few seconds:

    when flag clicked
    wait (2) secs
    forever
        create clone of [myself v]
        wait (pick random (5) to (10)) secs
    end

When each clone is created, you want it to appear in one of the 4 corners of the stage.

To do this, first create a new list variable called start positions and click the (+) to add in the values -180 and 180.

You can use these 2 list items to pick a random corner of the stage. Add this code to the ‘dot’ sprite, so that each new clone moves to a random corner and then slowly moves towards the controller.

    when I start as a clone
    go to x: (item (random v) of [start positions v]) y: (item (random v) of [start positions v])
    point towards [controller v]
    show
    repeat until <touching [controller v]?>
        move (1) steps
    end

The code above chooses either -180 or 180 for the x and y positions, meaning that each clone starts in one corner of the stage.

Test your project. You should see lots of red dots appear in each corner of the screen, and move slowly towards the controller.

Create 2 new variables called lives and score.

Add code to your stage to set the lives to 3 and the score to 0 at the start of the game.

You need to add code to the end of your red dot’s when I start as a clone code, so that either 1 is added to the player’s score if the colours match, or 1 is taken from the player’s lives if the colours don’t match.

    move (5) steps
    if <touching color [#FF0000]?> then
        change [score v] by (1)
        play sound [pop v]
    else
        change [lives v] by (-1)
        play sound [laser1 v]
    end
    delete this clone

Add this code to the end of your stage’s script, so that the game ends when the player loses all of their lives:

    wait until <(lives) < [1]>
    stop [all v]

Test your game to make sure this code works as expected.

Create a new variable called high score.

Click on your stage, and create a new custom block called check high score.

Just before the end of the game, add in your new custom block.

Add code to your custom block to store the current score as the high score if it’s the highest score so far:

    define [check high score]
    if <(score) > (high score)> then
        set [high score v] to (score)
    end

Test the code you’ve added. Play your game to check whether the high score is updated correctly.