Well I was going to say bring a book, but I remember several classes where I did that and would get yelled at. Strange thing was, I just ignored them, and I still got an A in those classes. I think they were mostly just mad because I was ignoring them. Fair warning though.
My senior year in high school I skipped 3 classes to play chess. But I also was clever about it and tricked my teachers into giving me permission to do it, and got A's in those classes. Lol, that reminds me of this one time in 9th grade. I think I sluffed at least one or two classes every day for the whole second half of the year, and only got caught twice. The first time I went to all my teachers and told them to sign a note saying I was at the class, then turned it into the office and got credit for attending the day. The second time I got caught was toward the end of the year. My punishment was to sit in the library and do all my work for the day I missed and the day I spent in the library, but being the end of the year that took about an hour and so the librarian just let me leave school. Rofl, that still makes me grin.