Scratch is a new programming environment that is designed to make it easy for students to put together a simple interactive computer program (think LOGO or Hypercard). With scratch students can start creating models after about 30 minutes of instruction. The main scratch page is scratch.mit.edu.
Why Programming?
Programming is an extension of drawing as a way for students to articulate their ideas. Programming allows you to take an image and include motion and interactions – two essential aspect of science. Students can draw a picture of an ecosystem or a chemical reaction, but if they can animate it or even simulate it, the ideas become far more articulated and the students understand more. Not only does scratch help students articulate their science ideas but they gain valuable technology and match skills in the process.Why Scratch?
Scratch was developed by some of the same people who created LOGO over 30 years ago. They have learned a lot about how to help students work with virtual objects and control their behavior. The result is a graphical interface where students program by creating stacks of interlocking bricks. There are bricks to create loops, to test conditions, to calculate values and to move objects. This makes the system easier to understand and harder to mess up. Scratch is free and works on almost any of computer (get the complete story at scratch.mit.edu).
Doing Science with Scratch
There are several different ways that students can interact with scratch. The simplest is to play with some of the science projects that have been posted to the scratch site. There are good projects on projectiles, vibrations, mitosis and many others. Students can explore these as they would any other simulation or applet. But the real advantage of Scratch is the ability to make programming accessible to students. To take advantage of this we really want students engaged in creating (or modifying) their own simulations of science content.
Take this project shark_v_tuna (you may need to right click this to download it) which has a simple predator-prey system. This project is not good yet, but it has the beginnings of a model. Students can expand and improve on this one without having to create the whole thing from scratch.
But there is a lot of value in creating a program entirely yourself (or with a group). Once students are familiar with scratch they can explore different ways to model their scientific phenomena.
We are currently working with some lesson plans and project ideas to fit the standards for different grades. If you would like to participate, join the working group.
To get started check out the main project editing screen (each program is called a "project").
Collumn 1 is the available programming elements (commands, tests, variables etc). Notice that each element has a particular shape so that it will only fit in certain place. Variables for example are ovals - so any command that calls for a variable has a space to fill in an oval. Categories of elements are motion, looks, sound, pen, control, sensing, numbers and variables.
Collumn 2 is the information for the selected sprite. Each object on the screen (including the "stage" background) is a sprite. Sprites can have scripts, costumes and sounds. Their are tools to draw costumes and record sounds (or upload them). The most important part are the scripts. Scripts are put together by dragging programming elements from collumn 1 together into the script for the current sprite. The peices snap together (if they fit) like legos. Start your scripts with a control element like "when the spacebar is pressed..."
Collumn 3 has the "stage area" (the white area where sprites can move) and the collection of sprites. Click on a sprite or the stage icon to access the scripts and cosumes for the sprite. At the top of the collumn are tools to move, copy, delete and change the size for any visible sprite.
The best way to learn is to go an play. Make a sprite, have it move in some way (e.g. follow the mouse, make a square, bounce around)
Here are some links for more information from the scratch site:
The summer workshop is exploring scratch by creating a computer model of a hopper (jumping toy picutred above). We will post the best models soon.
download the hopperstarter project
We do too! We are starting a Scratch Science working group here at CSUN. Science teachers who want to use Scratch with their students are urged to join this informal group. We will meet once a month on campus and communication online to help each other out. For more information contact Brian Foley (brian.foley@csun.edu)
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updated 7/2008