Sadly, Dr. E’s WeDo Challenges and Dr. E’s MINDSTORMS Challenges will no longer be posting new challenges. However, both websites will remain up so that you can continue to access the previous challenges and all of the wonderful submissions. Thank you to LEGO Education and to the Center for Engineering Education and Outreach at Tufts University for their years of support (and thank you to LEGO for their amazing robotics platforms). During the six years of WeDo challlenges and five years of MINDSTORMS challenges, we received almost 1000 submissions from around the world. The two websites had a total of 1266 registered users from 57 different countries. We were truly a global community! We have always been inspired and energized by the creativity and innovation shown by the Dr. E's Challenges community; while new challenges won't be posted moving forward, we hope that you continue doing awesome stuff in your homes, clubs, and classrooms and that you continue to share your projects with the world! Collaborating with all of you has been a joy and an inspiration. Thank you, The folks at Dr. E’s

Machine that draws and writes


 Lego machine made with we-do that draws and writes. Programs made by Jofre with Scratch 2. It can be controled with arrows in the computer keyboard or draw/writes pre-programed letters of shapes. The machine is a version of a technic machine by Isogawa Yoshihito with a few improvements to reduce vibrations and with a new pencil holder designed by Jofre.


 Frontal view of the machine.


 Top view of the machine.


Program to write the letter T made in scratch 2 by Jofre.


 Program to draw controlling with the arrows of the  computer keyboard with a scratch 2 program made by Jofre.



  1. bbratzel

    You did a great job of documenting your work–the pictures are excellent. So cool that you used Scratch, too. (But where is Iowa Pig?)

  2. High Tech Elementary

    We liked how you put a lot of work into it and how you used someone else’s open source idea. How could you make it go faster?Why did your robot go so slowly?

    -Second Graders at High Tech Elementary

    • GuillemiJofre

      It has to work slowly because it needs a lot of force to move a pencil and write or draw with accuracy (think about small kids learning to use a pencil!). Our first attempts failed because the pencil moved in jumps when pushed too fast. So the mechanisms with the two worms are needed to get this strong force. As a consequence, we got lots of vibrations and movement of the paper sheet which was avoided with further modifications to the machine. We added the red and blue long pieces that joined together maintain the shape of the whole thing and also we added a special lego technic piece (the large black one in one of the ends) which is has an unusual large weight (is the LEGO Part – 73090b Brick 2 x 6 x 2 Weight ). With these modifications is able to draw and write with a very good accuracy as controlled by scratch but in small format of course. We planned to try with a brush instead of a pencil (the force will be smaller so we can move it faster) but it was not clear to us how to control the amount of ink to be used. With a given power, you have to select to get force or speed. We selected force! (we feel the force, you know the power of the force!!)

Leave a Reply