(By the way, these are all technically middle grade (5th-8th) but some could go a little younger or older. If you aren't sure feel free to ask me. =)
-The Penderwicks by Jeanne Birdsall- this series is one of the happiest discoveries I've made in a long time. These books are so sweet and funny and I love that they feel old-fashioned even though technically their setting is present day. The story of these four sisters is so good from book one to book four.
-The Wednesday Wars by Gary D. Schmidt- I know I've mentioned this book like a million times here but I can't help myself. It's just so good. An English teacher, Shakespeare, the Vietnam War, middle school- it's hard to describe but just get it for your kids. I promise they'll love it. (All my students did.)
-The Templeton Twins Have an Idea by Ellis Weiner and Jeremy Holmes- I read this a couple years ago and immediately started reading it out loud to my sixth graders. The story of these clever twins who have to outwit a crazy stalker/wannabe kidnapper is told by a ridiculously hilarious and sarcastic narrator and it's just great. I need to read the sequel!
-The Crossover by Kwame Alexander. I'll be honest- I was skeptical about a book written entirely in poetry form (mostly free verse) but this story of a middle school basketball player with a famous dad who played professionally and a brother who is equally talented on the court is really great and the structure makes it move quickly. Hand this to a sports-loving boy to prove that poetry can be cool too. =)
-The Chronicles of Narnia by C.S. Lewis- I just finished reading these to Alice (her last feeding at night is the only time she'll be still long enough for long chapters =) and it was actually my first time to read the entire series. Ugh... all the heart eyes. They are just beautiful and I got choked up several times thinking of the allegory of Christ. These are great read-aloud books.
-The One and Only Ivan by Katherine Applegate- I saw this recommended on Janssen's blog ages ago but I was like, "a story about a gorilla? Nah." But a few weeks ago at the library I just happened to pick it up and I fell in love with the story immediately. Ivan and his elephant friend are part of a mall-front "circus" and his telling of their life in captivity is sweet and heartbreaking at the same time.
Additional suggestions: Harry Potter, anything by Roald Dahl, anything by Beverly Cleary, anything by Gary D. Schmidt, Jordan Sonnenblick, or Kristin Levine, the Dear America Diaries, or any Newberry winners. Oh, and Nancy Drew is always a good idea. =)
-The Boys in the Boat (Young Reader's Adaptation) by Daniel James Brown- this is one of my favorite books from the past few years. It's the story of the 1936 U.S. Olympic rowing team from the University of Washington and takes a close look at each team member, particularly Joe Rantz. It seamlessly weaves biography and history with a detailed look at the sport of rowing (which is super intimidating!) and I think boys especially will love it.
-Unbroken (Young Reader's Adaptation) by Laura Hillenbrand- this is a difficult story to read, even tailored to young readers, but it's so important for kids to be aware of the amazing sacrifices that American heroes have made on our behalf. The story of Louis Zamperini is nothing short of astonishing and definitely something that older kids and teens should learn from and be inspired by.
-Chasing Lincoln's Killer by James L. Swanson- this is a detailed narrative of the race to catch John Wilkes Booth, starting with his plot to shoot the President and ending with his apprehension in a barn miles away. It amazes me that the military was able to put together such a detailed investigation with basically none of the technology available today. Pretty much all of their clues were based on eye-witness accounts but they put the pieces together regardless. Fascinating stuff!
-BOMB: The Race to Build- and Steal- the World's Most Dangerous Weapon by Steve Sheinkin- oh man, this is SO good. The story of the journey to the atomic bomb and the countries involved in developing it (and the spying involved in the process) from the perspectives of the Americans, Germans, and Russians, reads like a novel but is totally true.
Some great biographies are the Heroes of the Faith series and the "Meet" series (Meet George Washington, Meet Benjamin Franklin, etc. These are especially good for younger readers.)
Oh, and one more thing- I highly recommend audio books, especially for struggling readers. I would definitely recommend getting an audio book AND a physical copy of the same book to allow your kids to follow along. OR if you can't get everyone to sit still long enough for chapters (and don't have the energy for reading with expression and doing a bunch of voices!) audiobooks are great for road trips. (Here is a great post about why you should try audiobooks with your kids.)
There you go! I hope this helps with the young readers in your life, but let's be honest- I've read and enjoyed them all so either I have the emotional level of an 11-year-old OR perhaps they're all just really great. (Let's go with the latter.) I LOVE hearing from you guys when you read something I've recommended so let me know if you check these out with your kids! Happy reading!