The Lion the Witch and the Wardrobe, Prince Caspian, The Voyage of the Dawn Treader, The Silver Chair, The Horse and His Boy, The Magician's Nephew, and The Last Battle by C.S. Lewis.
The White Mountains, The City of Gold and Lead, The Pool of Fire, and When The Tripods Came by John Christopher.
The Hobbit, The Fellowship of the Ring, The Two Towers, and The Return of the King by J.R.R. Tolkein (I read them when I was young).
To Kill A Mockingbird by Harper Lee.
The Adventures of Tom Sawyer, The Adventures of Huckleberry Finn, and A Connecticut Yankee in King Arthur's Court by Mark Twain.
A Tale of Two Cities, Oliver Twist, and David Copperfield by Charles Dickens.
Treasure Island, Kidnapped, and The Black Arrow by Robert Louis Stevenson.
A Wrinkle In Time, A Wind in the Door, and A Swiftly Tilting Planet by Madeleine L'Engle.
The Outsiders by S.E. Hinton.