Well, even if all these modern conveniences were available when I was a ***, it would be no use since back then we weren't allowed to bring drinks into the classroom in the first place. But since I always tried to get me a seat next to the window, that's where I'd write notes
haha, we used to just take water bottles, remove the label, write what we needed on the back then replace it on the bottle. when it came time for the test, you just looked through the clear bottle at your notes on the inside.