Maybe the computer was locked by one of their friends?! If there is a written rule against locking computers then just follow it. Nothing wrong with pissing others off.With the PIC friendly folks, you probably get more conversation by avoiding the whole Arduino thing. With other students though, tell them what they can do with arduino. There is so much you can do with it so anyone already interested in engineering or programming would be happy to know about it. I see a lot of things such as curriculum as backwards now that I have used arduino for a while. There is this programming in C class I'm sure every school has, where all you do is programming for programming sake, counting coin example every semester. Kind of like "theoretical" English, just learning syntax and dialogs. Would be a thousand times more interesting and useful if it involves an example or two with arduino. It tells you what you can do with even intro to C level of skills. Same as EE. Endless circuits problem with nodal analysis and Thevenin theorems for a whole semester while lots of these kids can't even build a voltage divider on a breadboard. What a shame to not be able to do the most basic circuit? With arduino you can instantly turn a voltage divider into a resistor sorter and students would be happy to sort out a bunch of random resistors with their skills. How can we integrate PIC in this picture? Maybe it's doable with PIC but you don't get to use a PIC until 2-3 years into your program. I'm going with the sure thing, arduino.
If you and your prof did your jobs, you'll know enough about solving problems with microcontrollers that you can adapt to the specific tools at hand.
Pretty difficult with just one MCU class one semester just my 2 cents. Only those motivated to do more will learn more.