How to Broadcast a Message in Scratch

One method to direct the timing of events in a coding project is to broadcast a message in Scratch. Broadcasting sends a message to one or more sprites. The message is used to trigger a script to run.

broadcast a message in scratch

Broadcast a message in Scratch to direct the timing of events.

Scratch Coding Blocks to Broadcast a Message

Scratch is a coding app that introduces programming concepts to beginners. It uses blocks of instructions that are joined together to build scripts. Scratch has several coding blocks that can be used for broadcasting messages.

broadcast block Send a message to sprites.
broadcast and wait Send a message to sprites. Pause until all scripts triggered by the message have finished running.
when i receive Run a script when a broadcasted message is received.

When Should You Broadcast a Message in Scratch?

Broadcasting controls WHEN something happens – it is all about TIMING!

To understand its use, compare broadcasting to other computer-related tasks. For instance when video editing, objects are sequenced into a track on a Timeline. Or when designing a graphic story in PowerPoint, events are timed using the Animation Pane.

Scratch does not have a Timeline or Animation Pane. Instead, instructions are sequenced using coding blocks. Broadcasting blocks are used to set the timing of events in an animated scene, game, or story.

What can you do with broadcasting?

  • Hold a Conversation: Have sprites chat with one another in an animated scene or story. Broadcasting can prompt a character to answer a question. Or, cause a character to respond to something that was said.
  • Respond to Events: Use broadcasting to make a sprite react to an event. For example, a character may move or change appearance when something happens.
  • Produce Multiple Actions at the Same Time: Broadcasting can send a message to many sprites. This can cause several characters to do something at the same time. This enhances storytelling and holds viewer interest.
  • Control Game Play: Direct when a game begins using broadcasting. After the instructions appear on the screen a broadcasted message can launch the game. Use it to make targets appear or start a timer.
  • End a Game: Set what happens when a game is over. Use broadcasting to inform a player that the game has ended. For instance, you could display a message, such as GAME OVER. Broadcasting can also be used to stop game play. For example, you could hide targets to prevent the player from scoring more points.
  • Organize Scripts: Long scripts in Scratch cannot display on one screen. This makes them difficult to debug. A solution is to divide the script into smaller chunks using broadcasting. (TechnoCode, a recent STEM project by TechnoKids for middle school grades, has an extension activity that explains how to organize scripts using broadcasting. )

Plan to Broadcast a Message in Scratch

When using broadcasting it is a good idea to PLAN AHEAD:

  • Decide what you want to happen.
  • Once you have an idea, pick the sprite that will send the message. Who is in control of when an action happens?
  • Study the sprite’s script. To send the message at the right time, where should the broadcast coding block be placed?
  • Next, pick the sprite or sprites that will receive the message. What will they do when they receive the message?

Broadcasting Video

Watch the video to understand how broadcasting can be used in graphic storytelling. If this is a coding project that you would like to make, TechnoCode has an animated storytelling coding unit. The instructions explain how to build scripts to illustrate events. The lessons also include a story organizer, checklist, coding journal log, Scratch quiz, and story rubric.

How to Broadcast a Message in Scratch

  1. Select the sprite that will send a message.
  2. From the Events palette, add the block broadcast message1.
    broadcast block
  3. Click the arrow. Select New message.

    Pick New message.

  4. Type message name. Click OK.

    broadcast message

    To make it easy to identify, give a broadcast message the name of the action it will trigger.

  5. Place the broadcast block where you want to send the message. For example:

    broadcast warning sample

    Place the broadcast block into the script.

  6. Select the sprite that will receive the message.
  7. From the Events palette, add the block when I receive message1. Click the arrow. Select the message name from Step 4.
    when i receive

  8. Build a script that has the sprite do an action. For example:
  9. say warning

    What do you want the character to do when it gets the message?

TechnoCode and Broadcasting in Scratch

TechnoCode has many programming lessons for kids. One of the coding units teaches graphic storytelling. Detailed instructions explain how to use broadcasting to direct the timing of events. Another coding unit is about game design. Broadcasting is used by students to trigger the start and end of a game. Learn more about programming for kids.

broadcast game over

TechnoCode has lessons that teach broadcasting in storytelling and game design.

Free Holiday Ecards for Kids, Promote Digital Literacy

Are you interested in free holiday ecards for kids? Take a look at Greetings Island. It has a collection of greeting cards and invitations that can be downloaded, printed, or sent online.

Have your children or students send electronic greeting cards to friends, family, or classmates. Ecards are a great way to let someone know they are important. The gesture of sending a greeting card can mean a lot to the recipient. It can also help people stay connected.

Aside from the personal connection, sending ecards has educational value. Children can practice their writing skills. In addition, it is a relevant way to communicate digitally with others.

Free holiday ecards for kids are a great way to promote digital literacy.

Have Fun Sending Free Holiday Ecards for Kids

What makes Greetings Island a fun place to send ecards?

  • Fast and Easy! It is simple to make a card. The icons make it easy for young children to know which options to select.
  • Personalize It: Kids can upload a photo from their device. This adds a personal touch.
  • Suggested Greetings: Emerging writers can select from a bank of text options, without having to write their own message.
  • No Email Address Required: If the sender is too young to have an email address, they can download the ecard or print it instead.
  • Lots of Choice: Holiday greeting cards are fun to send – but so are Get Well, Good Luck, Teacher Appreciation, and Thank You cards. Greetings Island has a wide range of categories.

Tips for Getting Started with Sending Free Holiday Ecards for Kids

Before you start having everyone in your classroom or home sending ecards, you should visit Greetings Island first. Explore the site to view the selection in the online collection. This will help you to direct younger children to appropriate categories. For example, Funny has some cards that include text or images that might not be suitable for your age group. However, the category Kids has some great options that kids will like to send. If you want more options for sending ecards, check out Free E-Card Sites for the Classroom.

Since Greetings Island is free, there are advertisements. Some ads link to different card sites. This can be confusing to young users. It is recommended that before having your students or children create ecards, give them a quick tour of the site. Help them to differentiate between an advertisement link and a card selection.

Ecards and Digital Literacy

Ecards are one way to promote digital literacy. You may also want kids to send email, chat, or post on social media safely. TechnoInternet has many activities designed to teach safe online practices.

digital literacy activities for kids

TechnoInternet has a collection of digital literacy activities for kids.

Adjust Graphic Effects in Scratch

Adjust graphic effects in Scratch to change the appearance of a sprite. Scratch is a coding app that can be used to introduce programming to children. It is free to use. Scratch has seven effects you can alter including color, fisheye, whirl, pixelate, mosaic, brightness, or ghost. Use the change effect coding block to enhance your projects.

Adjust graphic effects in Scratch.

Adjust graphic effects in Scratch.

TECHNOCODE TECHNOLOGY PROJECT
Tips are taken from the technology project TechnoCode. It includes a storytelling coding unit. Students explore the Looks palette to discover how to adjust the appearance of sprites. They apply their knowledge to animate an adventure in a strange or magical place. Instructional materials include a planning sheet, worksheets, example videos, sample scripts, story checklist, coding journal log, story rubric, Scratch quiz, diorama skill review, and extension activity.

Tips to Adjust Graphic Effects in Scratch

Ideas for Including Graphic Effects

Game Design

  • Attract Attention: Make a target easy to spot. For example, it could bulge using the fisheye effect when it appears on the stage.
  • Score Points: To show that a player has touched a target it could change its appearance. For example, it could distort using the whirl effect.

Storytelling

  • Create a Character: Perhaps your character is a ghost. Use the ghost effect to make them transparent.
  • Illustrate Action: Show an event. For example, if a character drinks potion maybe they change color.


Use Clear Graphic Effects

When you use the change effect the sprite alters its appearance permanently. To reset the appearance, add the clear graphic effects coding block to the script. For example:

Scratch script

Clear graphic effects to return the sprite to its original state.

Repeat the Graphic Effect

You can place the change effect inside a repeat coding block. This will cause a sprite to adjust its appearance many times.

repeat graphic effect

Repeat the graphic effect to have the appearance change many times.

Study the sample script above. You will notice it includes a wait coding block. This slows down the action, to make the changes easier to see. You will also see that it includes a clear graphic effects block at the end of the script to reset the sprite’s appearance (this coding block can also be placed at the beginning of the script).

How Much Should the Graphic Effect Change?

The change effect coding block has a value that can be set. What number should you use? Use the information in the table as a guide.

TIPS FOR SELECTING GRAPHIC EFFECT VALUES
color
  • Change the hue of the sprite.
  • positive values change the color in the following order
    green → blue → purple → pink → red → orange
  • negative values reverse the order from orange to green
  • explore the effect by changing the value by 20 or -20 each time
  • color changes depend on the original color- if the value is 25, a blue sprite will change to purple; whereas a pink sprite will change to red
fisheye
  • Bulge or shrink part of the sprite.
  • positive values expand the sprite to make it bulge
  • negative values contract the sprite to make it shrink
whirl
  • Twist the shape of the sprite.
  • positive values twist the sprite to the left
  • negative values twist the sprite to the right
pixelate
  • Divide the sprite into colored squares.
  • greater values display the sprite as a few big squares
  • lesser values display the sprite as many tiny squares
mosaic
  • Display multiple copies of the sprite in an array pattern, such as 4 x4.
  • greater values have bigger arrays with many duplicates of the sprite
  • lesser values have smaller arrays with a few duplicates of the sprite
brightness
  • Lighten or darken the sprite.
  • positive values increase the brightness
  • 100 turns a sprite into a white silhouette
  • negative values decrease the brightness
  • -100 turns a sprite into a black silhouette
ghost
  • Make a sprite transparent or see-through.
  • values can be between 1-100
  • 100 is fully transparent and removes the sprite from view
  • 1 is opaque which means it is solid

Scratch Activities, About the Stage, Draw with the Pen

When completing Scratch activities your students will benefit from understanding ordered pairs. This is a mathematical concept that is often not taught until the higher grades. However, it is knowledge that will help young programmers. It can be used to place sprites on the stage by setting the x and y values. It also helps when debugging scripts to determine why the positioning or movement is incorrect.

NOTE: The information in this blog article is from TechnoCode. TechnoCode includes Scratch activities that are ideal for beginners.

X and Y Coordinates

When you place a character on the stage, the Sprite pane shows x and y coordinates. They tell where the sprite is on the stage. If you drag the sprite, the numbers change because the position is now different.

Scratch activities

The X and Y coordinates tell where a sprite is on the stage.

Many Scratch coding blocks list x and y values. These coding blocks can be used to tell a character where to go on the stage.

go to x y  

How do you know the value of x and y? Where do you get the numbers?

About the Scratch Stage

You cannot see it – but the Scratch stage is divided into four parts. This is done using two number lines.

  • The x number line goes from left to right. It tells where a sprite is on the stage horizontally.
  • The y number line goes from top to bottom. It tells where a sprite is on the stage vertically.
  • The center of the stage is where the two number lines meet.
stage - Scratch activities for kids

The Scratch stage is divided into four parts.

What Is the X and Y Value?

Each part of the stage is made up of dots. Each dot has an x value and a y value that tell its location on the stage.

  • The x value tells you how many steps to move right or left from the center point. If the number is positive, move right. If it is negative, move left
  • The y value tells you how many steps to move up or down from the center point. If the number is positive, move up. If it is negative, move down.

Look at the picture below. Where is the dot on the stage? First, count across to get the x value. Then count up or down to get the y value. It is at x: 150, y: 100.

Scratch stage with dot

Where is the dot on the stage?

Where Is the Sprite on the Stage?

The x number line starts at -240 and ends at 240.

The y number lines starts at -180 and ends at 180.

By setting the x and y value for a coding block, you can place a sprite at a specific spot on the stage. For example:

  center of stage    x: 0 and y: 0

  right edge of stage    x: 240 and y: 0

  left edge of stage    x: -240 and y: 0

  top edge of stage    x: 0 and y: 180

  bottom edge of stage    x: 0 and y: -180

Scratch Activities for Kids – Use the Pen to Learn About X and Y

This activity is an excerpt from TechnoCode. The Scratch lesson includes four drawing activities designed to help students comprehend X and Y coordinates.

Drawing in Scratch is like doing a dot-to-dot puzzle. To draw a picture, build a script that puts the pen down at the first dot. Then move the pen from one dot to next. Try it!

Look at the picture of the Scratch stage. What are the x and y coordinates for each dot?

What are the X and Y values for each dot?

How to Draw a Square in Scratch

  1. Start a new Scratch project. Name it square.
  2. Select a sprite to use as a drawing tool.
  3. Resize the sprite to make it small.
  4. Delete Sprite 1.
  5. Click Add Extension. Select Pen.
  6. Build the script:

    About the script: Start when Go is clicked. Move to the first dot. Put the pen down to draw. Draw from one dot to another. See the square for 3 seconds. Erase the square.

Draw a square.

Scratch Activities – Sketch a Drawing

Drawing a picture in Scratch is like doing a dot-to-dot puzzle. In a dot-to-dot, each dot is numbered. A line joins one dot to the next. The lines form a picture.

Use your skills to make your own picture. Pick a suggestion or come up with your own idea.

  • triangle
  • rectangle
  • house
  • letter (T or E)
  • zig zag line

Download the Scratch Stage Worksheet

Download the Scratch Stage Worksheet. Sketch your idea for a drawing. Circle the “dot” at the beginning and at the end of each line. List the x and y values for each “dot” in the order they should be drawn.

TIP: Write pen up after a “dot” or x y value that should not have a line drawn to the next “dot” or x y value in the list.

Download the Scratch Stage Worksheet to plan your drawing.

Do You Need Help? Build the Script in Scratch

Are you stuck for ideas? If you are not sure what to draw, try building this script. What does it make? Use your coding skills to plan your own drawing.

letter

Want More Scratch Activities?

TechnoCode has over 30 assignments that explain step-by-step how to create animated scenes, games, and puzzles. Discover the fun you can have with Scratch!

TechnoCode

TechnoCode is jam-packed full of Scratch activities.