You can use the code here if you are stuck: https://scratch.mit.edu/projects/1136547961/

Introduction

Get ready to dive into an exciting project where you’ll learn the basics of physics and how gravity works—all through the fun and creativity of Scratch! This project is perfect for kids aged 8+ who have a basic understanding of force and gravity.

If you’re new to Scratch, don’t worry! Start by exploring these beginner-friendly tutorials:

👉 Scratch Getting Started

In this project, we’ll guide you step by step to build a game or simulation that demonstrates the effects of gravity on objects. You’ll learn how to:

• Use Scratch blocks to mimic real-world gravity.

• Create balls that fall, bounce, or move under the influence of gravity.

This isn’t just about coding—it’s about understanding how the world works through computational thinking. By the end of this project, you’ll not only have a cool Scratch creation to share but also a solid grasp of key physics concepts like motion, forces, and gravity.

Let’s build, learn, and explore together!

Setup the backdrop, sprites and the variables

Let's paint our backdrop and add a ball (circle) as the main sprite. Next, we will add a start button to trigger the random launch of the ball.

• Drag out "when green flag clicked" and set the start logic.

Below that, add the initial logic. Create variables x_velocity, y_velocity and gravity.

• "set [x_velocity] to (0)"

• "set [y_velocity] to (0)"

• "set [gravity] to [-0.1]"

  

Create a "start" button to send a broadcast message "start" to all the sprites. This is useful because we may have multiple ball sprites in the future.

Set the main code logic when the ball is launched

• What happens when the start button is clicked?

• Use random blocks to get starting speeds for x and y

• Move the ball down because of gravity - going down means the value has to be negative

  
  

Set the logic of handling the ball colliding with the edges - make the ball go in opposite direction with a small damp factor

• Set the logic of handling when the ball should stop. We can stop the ball if both the x velocity and y velocity falls below a certain threshold. Feel free to change the values used in the code above.

• Add simple sounds to make the simulation more interesting

• Check the video if you are stuck to implement the logic on your own

Extra Points

• Add another ball-2 sprite

• Let the ball2 use random starting position and fall independently of the main ball sprite

• Handle the collision of ball1 and ball2 using "sensing" blocks.

• What happens if we add 10 balls? Do you want to try it out?