"Charlotte's Web" by E.B. White: A truly beloved classic, but it's best for grades 1-4.
"All the Lovely Bad Ones" by Mary Downing Hahn: Ghost sightings & pranksters collide in this spooky mystery!
"Freak the Mighty" by Rodman Philbrick: Freak (tiny, disabled genius) + Max (huge & slow) = One Mighty Warrior!
"My Side of the Mountain" by Jean George: Tale of a boy who abandons city life for his dream of surviving nature!
"Frindle" by Andrew Clements: A funny novel about the perils & privileges of free speech... about a pen!