One school related item to keep your eyes open for is vintage (70’s and older) flashcard sets. Sets can sell between $20.00-$400.00. The ones that sell well have very interesting graphics or large “one word or phrase” reading cards.
It would definitely be to your advantage to look up “flashcards” on Ebay. This item often goes unnoticed in boxes at thrift stores, garages sales, and estate sales.
Finding these can be as simple as A-B-C!