Midnight for Charlie Bone (The Children of the Red King, Book 1)

by Trenton Lee Stewart

Like Charlie, your protagonist here is a gifted child recruited into an academy-like setting where his special abilities matter—except Stewart's gift is puzzle-solving rather than photograph-hearing. The real kinship is in how both books balance the cozy, slightly eccentric found-family dynamics of the school setting with genuinely creepy antagonists lurking in the background.

by Diana Wynne Jones

Jones has that same gift Nimmo does for making magical systems feel lived-in and matter-of-fact—nobody stops to explain the rules because everyone's too busy dealing with the chaos. The protagonist discovers hidden abilities while navigating a world where magic is woven into everyday life, and there's that same blend of whimsy and genuine peril that makes Bloor's Academy so compelling.

by George MacDonald

Here's your surprise pick: this reads almost like a literary character study wrapped in fantasy trappings. Like Charlie, your protagonist is an outsider suddenly thrust into an institution full of complex social hierarchies and hidden agendas, but Addison focuses on the emotional and political intelligence required to navigate it rather than action. It's quieter than Nimmo, but the sense of being watched and tested is just as palpable.

by Carlos Ruiz Zafon

Published in 2001 but set in post-war Barcelona, this one's from a different era entirely. Like Charlie uncovering secrets through photographs, your protagonist here becomes obsessed with a mystery hidden in a library's forgotten book—and both stories understand that the real magic is in piecing together what adults have deliberately hidden. Zafón's prose is richer and more atmospheric, but that same sense of a young person discovering dangerous truths applies.

by Jonathan Stroud

Stroud builds his magic system with the same logical precision Nimmo does—there are rules, consequences, and a whole hidden world operating alongside the mundane one. Your protagonist here is a young magician's apprentice navigating a London where supernatural power is currency, and like Charlie, he's constantly discovering that the adults around him are far more complicated and dangerous than they first appear.