SCRATCH Lesson 9: From Stories to Animations Part II

In Part II, I will show you how to add scene transition to your animation using broadcast message and “wait” control blocks.

A Stage is Like a Sprite

A Stage is like a Sprite. A Stage can change its look, just as a Sprite. A Stage can also think (such as doing math) and feel (such as checking if a sprite is touching another on Stage), just like a Sprite. Both Stages and Sprites can send and receive “messages”, which will be covered in this lesson.

The main difference between a Stage and a Sprite is that a Stage cannot move. Other than that, a Stage is just like a Sprite. I am already repeating myself but the following illustration should make this painfully clear.

A Sprite changes costumes.

A Stage changes backgrounds.


Both a Sprite and a Stage can think and feel.

Moreover, both Stages and Sprites can send and receive “messages”.

2: Scene Transition and Broadcast Messages

First, we need to design the story board.

Next, we will use Broadcast Messages to let actors (sprites) know when and where to move.

Introducing Broadcast Messages

Each scene has a set of sprites and each sprite needs to know where to go in a scene. Moreover, some sprites do not show up in some scenes. To let sprites know when and where they will go as scenes change, we will use Broadcast Messages.

A Broadcast Message is a message sent by a Sprite or a Stage, and can be received by all Sprites. We will let Stage send out Broadcast Messages. Click Control button from the Tool Kit.

Drag out a “broadcast” block from Control Took Kit and drop it in Stage’s Script Editor. Click the little down arrow and select a message or create a new message.

To create a new message, click the “new…” from the popped bubble and then enter “school” as message name. Click “OK” to save this new Broadcast Message.

In total, we need these messages: “To School”, “To Village”, “To Training Ground”, “To Fighting Stage”, “Done Laughing”, and “Done Training”.


Stage would change to “Village” background and sends out a “To Village” broadcast message (to everyone). Upon receiving the “To Village” message,

When Bobby shows up on Stage; all other sprites just hide.