Yeah, all the time in 6th Form, although it's less of a big deal there depending on the teacher.
I fucking hated politics and knew I was dropping it at the end of the first year so I stopped going, one time I went to hide out in a computer lab and kill some time... and walked straight past the entire class and teacher who had been in there for about half an hour doing some computer related assignment. Whoops.
There was one free period I had every week when everyone else was in class and it was boring as hell, so I used to go to woodwork with one of my mates and dick about with the tools, sanding bits of wood down to nothing and general dicking about. The teacher was so old and senile he not only didn't work out I wasn't one of his students, but he kept asking how my project was coming along...