Terry Pratchett is one of my all-time favorite authors, and his Tiffany Aching books hold a special place in my heart—both because the series is actually aimed at kids and teens, and because the last book he ever wrote was the final Tiffany Aching novel.
Wee Free Men is the first in the series, set in Pratchett's sprawling Discworld universe—and don't worry, no background Discworld knowledge is necessary going in. As I've always found quotations the best way to pitch Pratchett to new readers, enjoy an introduction to our no-nonsense heroine, Tiffany:
“No,” said Tiffany patiently. “[My question] is about zoology.”
“Zoology, eh? That's a big word, isn't it.”
“No, actually, it isn't,” said Tiffany. “Patronizing is a big word. Zoology is really quite short.”
If you're a fan of humor, coming-of-age stories, fantasy, or any combination of the above, I strongly recommend Wee Free Men—it's an absorbing and hilarious read, great for anyone 10+.