Why is the screen rotating?

Has this happened to you? The students are working and their screen changes orientation so that it is sideways or upside down. They profess amazement. What has happened is that the student has used one of Windows' shortcuts (link here if you want to know about it). It could have been an accident, but I have noticed that at the moment this knowledge is quite current among our students. My approach is to gently remove the computer from the culprit and the rest of the class decides not to follow suit.