Creating a Simple Drawing App in Scratch Jr

What a great project! Creating a simple drawing app in Scratch Jr is a fantastic way to introduce young learners to programming and creative expression. Here's a step-by-step guide to help you get started:

Prerequisites:

• You have Scratch Jr installed on your device (a free app available for Android and iOS).
• You have some basic knowledge of Scratch Jr, such as creating sprites, setting up stages, and using blocks to program.

Objective:

Create a simple drawing app that allows users to draw shapes (lines, circles, squares) using the mouse or touchscreen. The app should include features like:

1. Shape selection
2. Color choice
3. Drawing area
4. Eraser option

Step 1: Create the Stage and Sprites

• Open Scratch Jr and create a new project.
• Set up a stage with a background color of your choice (e.g., white or gray).
• Create three sprites:
  • A "Shape" sprite that will serve as the drawing tool.
  • A "Color" sprite that will allow users to choose colors.
  • An "Eraser" sprite that will help clean up drawings.

Step 2: Set up Shape Selection

• Use blocks to create a menu system for shape selection. For example, you can use the when green flag clicked block to trigger the menu and then use forever loops with if-then statements to cycle through shapes (e.g., lines, circles, squares).
• Use the ask block to prompt users to select a shape.

Step 3: Implement Color Choice

• Create a color palette by using blocks to generate different shades of colors. You can use the set pen color to block and then combine it with forever loops and if-then statements to cycle through colors.
• Use the ask block again to prompt users to select a color.

Step 4: Create Drawing Area

• Set up a drawing area by creating a sprite that serves as the canvas. You can use the stamp block to draw shapes onto the canvas.
• Use blocks to implement the drawing functionality:
  • When the user selects a shape and color, the app should set the pen color to the chosen color and the shape to the selected shape.
  • The app should then use the stamp block to draw the shape onto the canvas.

Step 5: Implement Eraser Option

• Create an eraser sprite that serves as a clearing tool. Use blocks to implement the erasing functionality:
  • When the user selects the eraser, the app should set the pen color to a default color (e.g., white or black).
  • The app should then use the stamp block with a clear color to erase the drawing area.

Step 6: Test and Refine

• Test your drawing app by running it on Scratch Jr. Make sure all features work as expected, including shape selection, color choice, drawing, and erasing.
• Refine your app as needed to address any issues or bugs you encounter.

Tips and Variations:

• Add more shapes, colors, or tools (e.g., text, images) to enhance the drawing experience.
• Implement a "undo" feature by storing the drawing history and allowing users to revert back to previous drawings.
• Create a save-and-load functionality to allow users to store and recall their drawings.

By following these steps, you'll create a simple yet engaging drawing app in Scratch Jr. Have fun exploring the world of programming and creative expression with your young learners!