[cbcase]

Reusing exam/written homework problems is unquestionably lax, I'd agree, but I do not think that professors should be writing new programming assignments each year.

I worked as an undergraduate teaching assistant for intro programming classes at my school, and the amount of debugging (as that's what it is) that goes into designing a good assignment is extraordinary. We had a small collection of world-class teaching professors, and each time a new assignment was introduced, there were always problems. Some starter code didn't work for students A-E. Or a requirement was so ambiguous that solutions varied in a material way.

Like everything else, writing a really excellent assignment is an iterative process. After two or three offerings, you finally have something your users (ie, students) really value: an assignment that teaches well.

And to be honest, the presence of cheating on programming assignments never made any sense to me. It's so simple to detect plagiarism: you have the source right there (and a database of all previous submissions). I really do think that CS stands out among the classes for plagiarism because of how much easier it is to spot rather than an unusual incident rate.

[blangblang]

^Like everything else, writing a really excellent assignment is an iterative process. After two or three offerings, you finally have something your users (ie, students) really value: an assignment that teaches well.

New assignments should be just that, another iteration on the original, excellent assignment. I had a few assignments in undergrad for which even solutions to previous versions were essentially useless unless you understood the underlying principles. The professor made this quite clear from the beginning. Minor changes in input/intermediate/output structures and changing constraints on the expected solutions easily confound the copy-pasters. I think this method even enhanced the learning experience for me by highlighting early on how a subtle difference in an algorithm can make all the difference in the world.

[dagw]

At my University you had to be able to explain and answer questions on your assignments before they gave you a pass. So while it was possible to 'borrow' an old solution, if you didn't also study and understand the code before handing it in you'd quickly be found out when you failed to answer even the simplest questions about how the code works why it looks the way it does.