The Friends of the Boylston Public Library will be having their annual booksale on Memorial Day, May 30 from 9:00 AM-2:00 PM.
I cannot recommend this booksale enough.
The prices are not rock-bottom, but they’re still library-book-sale prices. However, the selection is usually excellent, and the volunteers are friendly and helpful. Also, the Boylston Public Library is the cutest library building in Central Massachusetts.
The library booksale is part of a larger Boylston Memorial Day commemoration: there’s usually a fair on the common, an extremely cute parade down the street, bouncy castles, horse rides, etc.
In other words, bring your mother-in-law to supervise the kids while they play and gorge themselves on cotton candy while you shop for books.
(That also means that you might have to park far away from the booksale, which discourages you from buying two boxes’ worth of books.)