Using MIT Scratch for Programming and Control Exercise 1 Creating movement

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Using MIT Scratch for Programming and
ControlExercise 1Creating movement

• Year 9 ICT
• Autumn Term 2007

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What you will learn

• In this exercise we will learn
• How to create a simple movement programme (called
  a script in programming language)
• How to make the sprite reverse in direction
• How to make the movement go forever (until we
  stop the programme)
• How to make the sprite walk on the screen using
  costumes

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Simple movement

• One of the easiest programs to make is one that
  moves a figure on the screen.
• In Scratch the figure is called a Sprite.
• By default the sprite is a cat but there are many
  other sprites that we can use and that we will
  see later.

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Simple movement

• Click on the Control button shown on the left
• A series of commands will appear below the topics
  box.
• Select the first one (when flag is clicked), and
  drag it to the Scripts area of the screen.

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Simple movement

• Next click the Motion button (to the left of the
  Control button).
• Drag the move 10 steps button across and lock it
  underneath the earlier command. Your program
  should look like the one on the right.
• Click the green flag near the top right of the
  Scratch screen to run your program.

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Amending the program

• Now every time you click the green flag the
  sprite will move by 10 steps.
• You can change the amount of movement by altering
  the figure in the movement command.
• Double click on the value in the movement control
  and type in a new value.

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Changing Direction

• In this program we will make the sprite change
  direction. We will build on the program that we
  have created already.
• Change the movement value in your previous
  program from 10 to 40.
• Click the control option again and select the
  wait 1 secs command
• Click the motion button and add the point in
  direction 90 command below it.

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Changing Direction

• Click the motion button and add the point in
  direction 90 command below it.
• Click on the arrow beside the 90 and select -90
  from the list.
• Add another movement command and change the value
  to match the first
• Add another wait command, and then another
  'point' command.

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Changing Direction

• Finally, at the top of the screen where there is
  a small image of the sprite, click the middle
  button next to the image of the sprite. This
  makes the sprite change direction to match his
  movement

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Repeated movement

• Repeated movement (using forever)
• Often we want the sprite to be animated
  continuously until we tell it to stop.
• In order to get the script that we have written
  to loop use the Forever instruction.

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Walking sprite

• Click on the costumes tab note that the cat
  sprite comes with two costume
• Rename the sprite as cat
• Rename the costumes as Catwalk1 and catwalk2

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Walking sprite
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Walking sprite

• If you have followed all of the instructions
  correctly your sprite should walk backwards and
  forwards across the screen
• Save this project is your user area with the file
  name catwalk1