May 09

NOTE as of May 2013:

New! Scratch 2.0 is available in HTML5 format without the need for a download like Scratch 1.4. Just press the create tab.

You currently CANNOT use Scratch 2.0 for LEGO WeDo. Please download Scratch 1.4.

Quote from Mitch Resnick 05/10/2013:

“Thanks for your message.

We definitely plan to support LEGO WeDo with Scratch 2.0, but it probably won’t be available for a few months. We plan to support WeDo as part of a more general “extensions” mechanism, which will allow people to download packages of “custom blocks” for specific external devices (like WeDo) or web services.
When the new features are available, we’ll announce them on the Scratch and ScratchEd websites.


I have been Scratch-ing with LEGO WeDo kits, and my high school level students absolutely love it!
The LEGO® Education WeDo™ robotics kit is normally ear-marked as an elementary school product, and Scratch was developed by MIT for young children to be able to program, but the combination of the two has tapped the interest of my elementary school daughter, my middle school son, and my Computer Science students at the high school level.


LEGO WeDo USB and the ScratchEd Screen

The LEGO WeDo construction kit runs about $130.00, and Scratch Software from MIT is free (download Scratch 1.4). LEGO Software is available for younger students, but Scratch programming has inherent drag-and-drop blocks that resemble MIT App Inventor interfaces for Android Phones that my advanced students have been using. Directly plug in the LEGO WeDo USB to the computer with pre-loaded free Scratch drag-and-drop the robotics components will automatically appear in Scratch.
If you have a motor raising and lowering, you need to put an interface on the screen to explain what is happening, and if the interface is interactive, we are hitting the core-level of robotics understanding that we originally were going over student’s heads with NXTs because the software-hardware-interaction was not immediate.
An example program I created is called updownduck where a physical LEGO Duck is raised and lowered by clicking the words UP and DOWN on the screen. Scratch provides emulators where you can see the screen-programming in action (letters will change colors when you click them), but without the robotic LEGO WeDo motor and duck attached tethered to your computer, the program will not make sense to someone interacting with the screen (I have received comments saying that the program does not work from the sharing-Scratch community).

An example program using LEGO WeDo with Scratch called updownduck.

But when you download the Source Code and view it within Scratch, you can understand the purpose of the programming.

Source Code for updownduck in Scratch.

The ScratchEd website also has Introductory Tutorials on how to use each WeDo Component:
Scratch Screen and LEGO Customized WeDo
Scratch Screen and LEGO Customized WeDo

Distance Sensor + Hub

Distance Sensor + Sprite

Motor + Scratch

These intro projects give easy-to-follow LEGO directions within the Scratch window.

My favorite section is the WeDo Starter Projects that provide downloadable Scratch files to utilize the Distance Sensor, The Tilt Sensor, and the Motor. We modified the motor project to lift a platform of LEGO Men provided from the WeDo kit. Our challenge was to create a way to make sure the platform stops at a safe level without knocking off the LEGO men.

Complex projects were created at the MIT Lab and you can download the Scratch Files:

  • Submarine Rescue – interactive adventure
  • Balancing Robot – I wish they would post the LEGO designs so we can build the same bot
  • King Duck vs. Fatman Protagonist -interactive balancing and storytelling
  • Caterpillar Love Story – AWESOME storytelling
  • Skiing Moose Ferris Wheel – I wish they would post the LEGO designs for the arm-swinging moose

Many of these projects require teachers or upper-level students to build the components, but once built the storytelling capabilities are incredible.

The robotic LEGO WeDo components that work in Scratch are a Distance Sensor, The Tilt Sensor, and a rotating Motor. The new Science Standards of Learning in Virginia indicate students must have an understanding of probeware, sensor, and accumulate data. The LEGO WeDo components also give numerical indicators on the Scratch Screen of distances and tilt values that can be transferred into authentic data. When the distance sensor shows a value of 2, students can measure with a ruler the distance and chart the values. When the tilt sensor shows a value of 3, students can determine how many degrees equal a value of 3.

NEW! (June 2013) There is now a LEGO WeDo Resource Set for more authentic examples of engineering (ferris wheel, crane, cars, and intelligent houses) versus the traditional LEGO Education WeDo Contruction Set (alligators, birds, and monkeys) for younger children.

UPDATE: (May 2013) This Project has won a RichTech STEM Educator Award!







(Sept 2012) This Project has won a Governor of Virginia COVITS Award!

Innovative Use of Technology in Education

Winner: Atlee High School
For: Scratch and LEGO WeDo for High School

ABOVE: Presenting SCRATCHing to the 21st Century at the DEN VirtCon 2012 with a special DEN VirtCon Scratch Gallery

SCRATCHing to the 21st Century Presentation Slide

2 Responses to “Scratch-ing the LEGO WeDo”

  1. Natalie Says:

    Greetings from the Scratch Team at MIT–we’re glad to hear how you’re making use of Scratch with LEGO WeDo functionality and resources in high schools. Congratulations on the Governor’s award!


  1. SCRATCHing to the 21st Century

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