Some do. Others do what what two of our students did, who I will call Tom and Jerry. The project involved writing some unit tests, and Tom had written a test for a function that took a string as its argument. For the test string, Tom used his name. When Jerry copied Tom's code verbatim, he changed a few things around, but made sure not to mess with the test code. It was pretty easy to figure out who Jerry got his project from. I couldn't believe it.