Your First Scratch Project

Scratch is a free programming environment where you build programs by snapping colorful blocks together instead of typing code. It was created by specialists at the Massachusetts Institute of Technology (MIT) for children and teenagers. You can use Scratch in a browser or install it on your computer.

The Scratch window has several parts. The stage shows the result of the project, and the characters, called sprites, move on it. Blocks are grouped into categories such as Motion, Looks, Sound, Events and Control. You drag the blocks you need into the scripts area and snap them together.

For your first project, take the “when green flag clicked” block and attach the “move 10 steps” and “say Hello! for 2 seconds” blocks under it. When you click the green flag, the cat walks forward and says hello. The script runs from top to bottom, block by block, just like a linear algorithm.

Now let us draw a square. Add the Pen extension, place the “pen down” block first, and put “move 100 steps” and “turn 90 degrees” inside a “repeat 4” block. The sprite draws the four sides of a square, because 4 times 90 degrees makes a full turn.

Key takeaways

• Scratch is a free visual programming environment where programs are built from blocks.
• Parts of the window: the stage, sprites, the block palette and the scripts area.
• A script is a sequence of blocks that runs from top to bottom.
• A repeat block runs the same commands several times without rewriting them.