Her children's books have been translated into Chinese, Danish, Dutch, German, Greek, Hebrew, Italian, Japanese, Korean, Persian, Portuguese, Spanish, and will be in Thai and Polish. Many of her children's books are retellings of fairy tales, including ''The Magic Circle'', ''Crazy Jack'', ''Spinners'', ''Zel'', ''Breath'', ''Bound'', ''Beast'', and ''The Wager'' for older children, and ''The Prince of the Pond'', ''Ugly'', and ''Mogo the Third Warthog'' for younger children. Other children's stories are historical fiction based in Italy, including ''Daughter of Venice'', ''For the Love of Venice'', and ''The Smile''. Napoli has won numerous awards for her work, including the Golden Kite Award given by the Society of Children’s Book Writers and Illustrators (for ''Stones in Water'', and honor book ''Breath''), the Sydney Taylor Award given by the Association of Jewish Libraries (for ''Stones in Water'', and, honor book, ''The King of Mulberry Street'' and the Parents' Choice Gold Award (for ''Alligator Bayou'' and Silver awards for ''North'' and ''The King of Mulberry Street'').
Her publications in linguistics include ''Syntactic argumentation'' (with Emily Rando). (Washington, DC: Georgetown Univ. Press, 1979), ''Syntax: Theory and Problems'' (Oxford: Oxford Univ. Press, 1993), ''Linguistics: An introduction '' (Oxford: Oxford Univ. Press, 1996), ''Humour in sign languages: The linguistic underpinnings'' (with Rachel Sutton-Spence) (Dublin: Trinity Press, 2009), with dozens of articles in the scholarly journals. She is a former member of the editorial board of the premiere journal ''Language''.