Scratch
Intermediate
60 mins
Teacher/Student led
+165 XP
What you need:
Chromebook/Laptop/PC or iPad/Tablet

Red v Green v Blue

In this project a hundred dots, consisting of red, green and blue, will randomly appear and float around the screen. Red dots infect green, green dots infect blue and blue dots infect red. They battle it out until one colour wins out!

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    1 - Create a new Scratch project

    Create a new Scratch project and delete the cat sprite

    2 - Create a red dot sprite

    Create a new sprite by clicking on the paintbrush, this will open up the sprite editor. To draw draw a red circle, follow these steps:

    1. Choose a red colour in the Fill tool
    2. Turn off the Outline tool
    3. Select the Circle tool
    4. Draw a small circle in the middle of the editor (hold down the shift key while you draw it to make it a perfect circle)
    5. Name this costume 'red'


    If for some reason you can't create the red dot sprite, you can just use this starter project which already has the backdrop added to it. https://scratch.mit.edu/projects/780048995

    3 - Create the green and blue costumes

    We now need to create two more costumes for this sprite, a green circle and a blue circle.

    Duplicate the red costume twice and then use the paint bucket tool to change the colour to blue and green.

    Don't forget to name the costumes 'blue' and 'green'!


    4 - Create a 'count' variable

    Now that we've created our sprite, let's start coding!

    We're going to code 100 dots to appear so we need a variable to let us count to 100. Using the Variables toolbox create a 'count' variable.

    Add the following code to your sprite to start 'count' at 0.

    when green flag clicked set [count v] to [0]

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