Crowd source a long list of Novel exit slip questions, have students suggest one for each day of a Lit Circle round (i.e. ask them which one we should all answer today): http://wildaboutfifthgrade.blogspot.ca/2013/10/using-reading-exit-slips-to-provide.html?m=1

The following are books that at least five students rated lower than a 6 out of 10 AND have a mean average below 7.0.

Jake and Lily
The Mostly True Adventures of Homer P. Figg
The Year of the Hangman
Replay
Beryl: A Pig's Tale
Hatching Magic
The True Confessions of Charlotte Doyle
Minerva Clark Gets a Clue
Animal Tales: Angus McMouse Brings Down the House
The Great Gilly Hopkins
The 13th Floor
The Teacher's Funeral
Skellig
Midnight Rider
Each Little Bird that Sings
How to Steal a Dog
The School Story
A Wrinkle in Time
A View from Saturday
The Small Adventures of Popeye and Elvis
The Tail of Emily Windsnap
Crispin
Gentle Ben
Sounder
The Gypsy Game
Everything on a Waffle
Tales of the Bronx
The Library Card
Coraline
Stones in Water
The Case of the Missing Marquess
The Year of the Hangman
Hope Was Here
The Cricket in Times Square
The Boy Who Saved Baseball
The Westing Game
The Anybodies

Presented in order of preference from 15+ years of ratings:

The One and Only Ivan
Skeleton Creek
Wonder
A Dog's Life
Juniper Berry
Harry Potter and the Sorcerer's Stone
Gregor the Overlander
The Wanderer
The Sister's Grimm 1
The Sea of Monsters (Lightning Thief Book 2)
Jackie and Me
The Brixton Brothers 1
Floors
Fever, 1793
Out of My Mind
Holes
The Phantom Tollbooth
Woods Runner
The Cay
The Miraculous Journey of Edward Tulane
Things Not Seen
The Tale of Despereaux
Chasing Vermeer
101 Ways to Bug Your Parents
The Watsons Go to Birmingham
Tuck Everlasting
The Brixton Brothers 2
Small Steps
A Corner of the Universe
The Genius Files
Princess Academy
Jeremy Thatcher, Dragon Hatcher
Wayside School is Falling Down
The Lemonade War
All the Wrong Questions
The Maze of Bones
The Homework Machine
The Book of Three
Lunch Money
Crash
Bud, Not Buddy
The Secret Language of Girls
Rules
Notes from a Liar and Her Dog
Stargirl
Kid vs. Squid
Framed
Swindle
Running Out of Time
Vincent Shadow: Toy Inventor
Among the Hidden
Timothy of the Cay
Among the Imposters
It Only Looks Easy
Joey Pigza Swallowed the Key
Once Upon a Marigold
Ida B
Double Fudge
Artemis Fowl 1
Fudge-a-Mania
Loser
Absolutely Normal Chaos
Number the Stars
Radio Fifth Grade

Vocabulary
Flashbacks
Changing Point of View or Narrators
Plot
Setting
Too many characters to keep up with

(Look at Lit Circle review cards)