Books about Friendship -- Juvenile fiction (sorted alphabetically)
- In the High Valley Susan Coolidge
- In the King's Name: The Cruise of the "Kestrel" George Manville Fenn
- It's like this, cat Emily Neville
- Jack and Jill Louisa May Alcott
- Jack and Jill Louisa May Alcott
- Jack Straw, Lighthouse Builder Irving Crump
- Jack, the Fire Dog Lily F. Wesselhoeft
- Jack Winters' Campmates Mark Overton
- Jack Winters' Gridiron Chums Mark Overton
- Jasper's old shed, and how the light shone in A. M. Coker
- Jessica's First Prayer; and, Jessica's Mother Hesba Stretton
- Jessie's Parrot Joanna H. Mathews
- Jimmy Boy Sophie May
- Jimmy, Lucy, and All Sophie May
- John Tincroft, bachelor and benedict : or, Without intending it George E. Sargent
- Joyous Story of Toto Laura Elizabeth Howe Richards
- Jungle and Stream; Or, The Adventures of Two Boys in Siam George Manville Fenn
- Just Gerry Christine Chaundler
- Just Patty Jean Webster
- Keeping His Course Ralph Henry Barbour
- King of the Park Marshall Saunders
- King's Daughters Emily Sarah Holt
- Kit of Greenacre Farm Izola L. Forrester
- Knights of the White Shield Edward A. Rand
- Kun me olimme tyttöjä (Finnish) Sarah Doudney