Yep, our daughter was like SL. She did her work in the living room with us. Placed her work back in the folder. of her back pack.. . returned graded papers were thrown in the recycle.. or she would keep them for a while, based on whether she would need the info for a test, or a report.
At the end of the school year she usually tossed all of it. We kept the things like special projects or some of the artwork, but mostly it was thrown away.
They were fortunate that many times they did not have to carry their subject books back and forth from home. There were classroom sets.. So her subject books were kept on her desk, so she knew where they were.
All of her school supplies were kept in the desk.. Paper, spirals, folders, pens, pencils..if we saw a good sale, we would purchase it so that there was no last minute, searching for school supplies. etc.
As she got older and took more advanced art classes, many of these art supplies supplies were kept in a basket in one of drawers/ cabinet of her desk.