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Scratch User Guide: Installing & Getting Started with Scratch

Scratch Tutorial Note

This user guide was written for Scratch version 1.4, which is available for download here. Additional tutorials are available on the download page.

The newest version of Scratch (2.0) is based on Adobe Flash Player, which will be retired in 2020 due to security flaws. Due to these security risks, Science Buddies has chosen not to update our projects to Scratch 2.0. While the projects will work in Scratch 2.0, the locations and apperances of some buttons and features in Scratch 2.0 may differ from what is described in this tutorial.

If you want to use Scratch 2.0, you can download an offline version here. If you must use the browser-based version (for example, you are using a school computer where you cannot install software), you can access it here. Note that you may need to enable Adoble Flash Player in your browser to get Scratch to work.

Installing Scratch

Scratch is a free, easy-to-use programming language from MIT that you can use to make all sorts of animated stories, art, music, and even interactive games. Installing Scratch is simple. All you need to do is go to the Scratch download page, http://scratch.mit.edu/scratch_1.4/, and follow the simple instructions there to download and install Scratch for free. Be sure you have permission to install the program on the computer you are using.

Getting Started with Scratch

  1. In addition to our own user guide, the Getting Started with Scratch guide and Scratch Reference Guide contain a lot of useful information. However, you do not have to sit down and read all this material in advance. It might be more fun to open up Scratch and just start playing around! Then, you can refer back to the reference materials when you need help or get stuck.
  2. Scratch has a very simple programming environment, made up of five main areas. Figure 1 shows where each of those areas is located, and Table 1 provides more details about each area.
Computer Science fair project Labeled in orange are the five areas of the Scratch programming environment. Also notice the green flag and red octagon icons, circled in blue. When the green flag is clicked, the program you've created runs in the stage window. Clicking the red octagon stops the program.
Figure 1. Labeled in orange are the five areas of the Scratch programming environment. Also notice the green flag and red octagon icons, circled in blue. When the green flag is clicked, the program you've created runs in the stage window. Clicking the red octagon stops the program.

Area Function
Scripting Area Within the scripting area, there are three tabs:
  • The Scripts tab is where you will drag and drop the blocks that make up the script(s) your sprite(s) will follow.
  • The Costumes tab is where all of the poses or looks a sprite can have are created. When writing scripts for the staging area (referred to as the stage), this tab becomes the background tab.
  • The Sounds tab is where different sounds and pieces of the music a sprite can use are created. The stage also has its own Sounds tab.
Each sprite that you create will have its own scripting area. The stage has one, too, and this is a good place to put scripts that apply to all sprites, as well as background-specific scripts.
Block Categories There are eight block categories. Notice that the blocks have different shapes. This gives you a clue about which blocks can be snapped together and which blocks can't be snapped together. If the shapes fit together, then they will work together.
  • Motion: These blocks are used to move the sprite around the screen.
  • Looks: The blocks listed here change the appearance of the sprite. For example, having the sprite say or think something changes the appearance of the sprite, so these blocks are included in the Looks category.
  • Sound: These blocks are used to add different sounds to the sprite's script. You can access the various sounds that you designed in the scripting area's Sounds tab with these blocks as well.
  • Pen: Use these blocks to write on the screen or to make drawings and patterns.
  • Control: This category contains the blocks that control the execution of blocks or a set of blocks. Included are "when" blocks, conditional statement blocks ("If" and "If/Else"), "forever," and "repeat." To use control blocks, simply drag the block into the script tab and then drag whatever other blocks you need into the control block. Note: in Scratch 2.0, some of these blocks have been moved to a new "Events" category.
  • Sensing: These blocks allow the sprite to interact with its surroundings and allow the user to interact with the program, using devices such as the PicoBoard or the Lego WeDo.
  • Operators: These blocks allow you to compare variables and sprite positions.
  • Variables: In this category, you can define different variables that you require in your program.
List of Blocks Once you click on one of the categories listed, the different blocks that are included in this category are listed.
Stage This is the area where the sprites execute or run the script that you built in the scripting area. Clicking on the green flag allows you to start executing the script (if you set up your script to do so) and the red button will make the script stop.
Sprite List There are three buttons here that you can use to create a variety of sprites and backgrounds.
  • The first button allows you to draw your own sprite, using various colors and tools.
  • The second button allows you to choose a sprite from a gallery of sprites, or a sprite that you generated on your own, either using a camera or from clipart.
  • The third button gives you a surprise sprite.
You can have as many sprites as you want in a single program. Clicking on an individual sprite shows you its scripting area. Clicking on the stage button sends you to its scripting area where you can add different backgrounds (scenery).

Table 1. This table lists all the functions available in each of the five Scratch programming environment areas.

  1. Scratch programs, also called projects, are created by dragging, dropping, and snapping together different blocks. All blocks that are joined together are called a script. Simple programs may have just one or two scripts, whereas more complex programs have many scripts.
  2. You now have enough information to get started writing scripts and experimenting with Scratch. Open up the Scratch programming environment and start playing around.
    1. For example, click on one of the menus in the upper left of your screen, like the Motion menu. In the screen below it, you will see all the commands that are available under that menu. Try clicking on one of the commands, like "Move" or "Turn" to see what happens to the cat sprite. Then change numbers inside the commands (for example, change "Move 10 steps" to "Move 30 steps") and click again on the command to see what happens to the sprite.
  3. If you'd like a more complete description of what each block does, read MIT's Scratch Reference Guide. This guide is very detailed and helpful once you have had a chance to play with Scratch a bit.
  4. If you have a specific question about how to do something in Scratch (like change colors, make a sprite jump, or keep score in a video game), try a Google search for "how to __________ in Scratch" (and fill in the blank with what you want to do). Many times, you will be able to find example code online, or forum posts discussing the same topic.

Step-by-Step Instruction Resources for Learning to Program with Scratch

One of the nice things about using Scratch is that there are a lot of people and places to turn to for help. If you get stuck programming, or are confused about how to start a specific project, consult the Science Buddies Help, I'm Stuck! Troubleshooting a Program in Scratch page. Table 2 also lists some additional options for learning more about Scratch or asking questions.

Type of Resource Citation
Book for beginners about programming with Scratch. Ford Jr., Jerry Lee. Scratch Programming for Teens. Boston: Course Technology, 2009.
Book for beginners about programming with Scratch. Badger, Michael. Scratch 1.4 Beginners Guide. Packt Publishing, 2009.
Official Scratch getting started resources (Scratch 2.0, but code will work in Scratch 1.4) https://scratch.mit.edu/tips
Scratch wiki with more information about Scratch https://wiki.scratch.mit.edu/wiki/Scratch_Wiki_Home
Scratch forum where you can ask questions https://scratch.mit.edu/discuss/

Table 2. Resources with step-by-step help for learning to program with Scratch.

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