Hooper's correspondence with her parents from 1912 to 1919 and her college photograph album are in the Smith College Archives. Hooper began donating her collections to various institutions in 1979, including a few works by Carl Linnaeus to Wellesley College. The following year, Hooper donated her extensive Kate Greenaway collection to the Hunt Institute and wrote an essay about her collection for their exhibition catalogue Kate Greenaway (Pittsburgh: Hunt Institute for Botanical Documentation, Carnegie-Mellon University, 1980). She gave the rest of her collection of works in English by and about Linnaeus to the Chicago Horticultural Society in 1982. First editions by other authors in Hooper's collection were donated to the University of Chicago after her death.