Yes, there are a few books I would use as abridged, too; and of those, older versions where possible and not usually literature. I think older authors (like the Robinson Crusoe written Anew) keep the flavor of the original better. Most literature is best waited for till they are mature enough for it, but there are a few.
Les Miserables
The Illiad, The Odyssey, Aeneid (I’m choosing the Rosemary Sutcliff versions this year, then either Alfred Church or Padraic Colum versions later)
A Plutarch starting at 10/11 (Our Young Folk’s Plutarch by Rosalie KAufman now then in high school, an advanced one)
Stories from Plato and other Classic Writers by Mary Burt
Beowulf adapted by H.E. MArshall
The Story of Roland by James Baldwin
Stories of Don Quixote by James Baldwin
The Story of Seigfried by James BAldwin
Beautiful Soties from Shakespeare by Nesbitt
Tales from Shakespeare by Charles and MAry Lamb
Aesop for Children by MIlo Winter
Herodutus history (one by Alfred Church)
Josephus history (one by Alfred Church)