Introduction to SCRATCH

SCRATCH is an activity that lets you play games, read stories, admire and interact with beautiful graphics. But SCRATCH is MUCH more than just watching… SCRATCH lets you make games, create stories, and learn how to use the computer to create beautiful graphics. Everything in SCRATCH is based on Sprites, Scripts, Costumes and Sounds. Most of the activities we will learn, use a single Sprite and Script. However it is important to realize that we can have more than one script operating at a time.

A sprite is just a picture… like the SCRATCH Cat. A sprite can have more than one costume… the Cat has two, which can be used to give the Cat a walking motion. You can also import sounds that can be used in a script.

A script is an object made up of Building blocks. The Building Blocks control everything that happens on the Stage, which is where the Sprite can move around. If you find a game or other SCRATCH activity that you like, take a look at its Script or Scripts. Once you learn to read Scripts, you will learn lots of ideas for creating your own.

Lesson 1: Building blocks:

  • Motion
  • Control
  • Looks
  • Sensing
  • Sound
  • Operators
  • Pen
  • Variables

Motion lets you place the current sprite (like the SCRATCH Cat) anywhere on the screen and then have it move and turn.

Controllets you choose when something is to happen. You can start, wait, repeat, and watch for and change when things you are watching happen.

Looks lets you change the “costume” for a sprite, control how big the sprite is, control cartoon speech or thought balloons and words, and make things go in front of or behind other things.

Pen lets you have your sprite leave a trail wherever it travels. You can control when the trail begins (clear [erase], pen up and pen down), the size of the pen, the color of the line, and the shade of the color.

To create a scratch program you build the “script”… like creating a LEGO design by plugging together different shapes, but THESE shapes are able to DO THINGS!

Motion / Control / Looks / Pen

Example of a simple script. Can you connect the segments so that the sprite moves around a square?

Can you add a building block so that the sprite draws a square?