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» writing

teaching machines

Letter of Reference

Dear ██████, I am writing on behalf of ██████, a former student of mine who is ready to strike out on his own after graduating this May. He has applied at your company for a Software Engineer III position and has asked me to provide a letter of reference. I wish to recommend him without […]

The Thrilling Adventures of Lovelace and Babbage

This is my third post in a series of reviews on technology-related graphic novels. I had hoped to participate in a special session on such novels at SIGCSE 2017, but the the special session was not accepted by the reviewers. *sniff* The Thrilling Adventures of Lovelace and Babbage is subtitled “the (mostly) true story of […]

Secret Coders

My foray into technology-themed graphic novels began with a book about consumerism, but now we turn to a book on what I call developerism—the insatiable need to design and make your own stuff using the computer. Gene Luen Yang and Mike Holmes have published two books so far in a series called Secret Coders, which […]

In Real Life

For SIGCSE 2017, I’m reading a bunch of graphic novels related to computer science and technology. First up is In Real Life, by Cory Doctorow and Jen Wang. I share here notes and reactions from my reading. Spoilers lie ahead. I have to write as much down as I can, because the book is due […]

Computer Science in High School

A student is working on a project about teaching computer science classes in high school and is trying to gather insights from folks about how it might be done. His questions and my answers follow. Could you give a quick overview of what your process is for implementing these classes? There’s a term sometimes comes […]

Changing Minds

I recently finished reading Andrea diSessa’s Changing Minds: Computers, Learning, and Literacy. My work on Madeup had me reading many books that mentioned this book, and I spent a good deal of time in diSessa’s earlier Turtle Geometry. So, it was only a matter of time before I read Changing Minds. In it, physicist diSessa […]

Navigators Talk

My friend and Navigators campus director Jeff Clochesy gave me the opportunity to speak at Nav Night this past semester. Nav Night is a weekly fellowship time of the Navigators campus ministry. I’m Chris Johnson, which rhymes with Wisconsin. For the past six years I’ve been teaching computer science at the college level. You folks […]

Generating Digital Audio for a Pitch

Sound is a wave of pressure that travels through the environment. My high school physics teacher Mr. Oppelt told me that pressure is force applied to a surface, and so when we say that music has a beat, we’re quite right. It “beats” on things. Like our ear drums. It beats on other things too, […]

Learning Elsewhere: Tales from an Extra-curricular Game Development Competition

Following is a draft of a talk I am to give at ITiCSE 2013. The work discussed was done several years ago at Iowa State University, during my first full year of full-time teaching. I wish I had more quantitative results, but its absence is sort of consistent with the premise that we cannot do […]