Archive for the ‘CS Circles’ Category

I wanted to post a short update on CS Circles, my project with the University of Waterloo CEMC to teach introductory programming online. I’ve been checking the total number of problems solved on the site, and it has just surpassed 750000! I’m pretty sure I’ve never done 750000 of anything in my life except maybe […]

Computer Science Circles is now fully open-source! Over the summer, we put the backend code up on GitHub and provided links to the lesson and exercise definitions on the website. A SIGCSE Special Projects grant made this work possible, for which we’re very grateful. One thing we learned as a result is that open-sourcing has surprising applications. […]

Hallo, Welt!


Computer Science Circles is now live in German! This awesome development is due to Wolfgang Pohl, Marcel Inhoff and the rest of the crew at BWINF. I am very excited and thankful for their hard work. Check it out here… you might be the lucky person to complete the 250000th exercise!

A Power Law


One of my advisees this semester, George Okeowo, investigated the error messages produced by Python, using a corpus of 600000 buggy programs submitted by students to the Computer Science Circles website. The project was focused on writing beginner-understandable versions of error messages, focusing on the most common errors. A side-effect of the investigation was to […]

In the last month there has been exciting news about the Computer Science Circles project I’ve worked on with colleagues from the University of Waterloo. One is that the site is now disponible en français, thanks in no small part to Brice Canvel, a Swiss teacher who translated most of the lessons. Another is that a paper […]

The animated .gif above shows the first program in Computer Science Circles, a project that I’ve been working on whose goal is to give everybody a good introduction in computer programming. We recently achieved our 1000th registered user, and had our 100000th piece of code submitted and run; we have about 100 distinct logged-in users per day. (Also, almost […]

The Computer Science Circles project that I’m working on has a lot of exercises and content, but has not had very much practical information in terms of debugging and design. Today as a partial remedy, I wrote a lesson called Design, Debugging and Donuts and added it to the site. It was an excellent excuse to […]