Not in the States, but in my neck of the woods, variations on the Duo-Tang filled more or less the same niche in the '60s and '70s. They could be had with insid

Not in the States, but in my neck of the woods, variations on the Duo-Tang filled more or less the same niche in the '60s and '70s. They could be had with inside cover pockets in addition to the three-ring binding fasteners and with three-ring punched "spines" to be added to a more substantial binder. So you had an expandable notebook (that could hold plain, lined and graph paper as appropriate for the page) along with holders for loose scraps - and turning in your notebooks now and again for marking was a thing.