For the record (or whatever) I used to keep a set of composition notebooks like paper-machine describes. They got to be a really huge number, some of them redundant, most of them mostly empty or only a third full. A few of them got to the point of being all the way full and spread into a second volume. They mostly contained lecture notes from my college classes, sometimes I'd get up the energy to add additional notes from studying into them. I threw them out sadly, a few moves ago, when I was depressed and cutting down on my possessions to try to get more control over fewer of them. That was my rationale at the time, anyways. There wasn't much of a system of organization to them though, except that it would be one subject per notebook, summaries of whatever I was studying on one thick column and notes about it or things that popped into my head while I was listening or reading in the other column.