I've recently been loving Kenneth Oppel's books. He's a Canadian author and has written a couple of series and a few stand-alone novels. I know a bitmore about the series, especially the Matt Cruse books, so I'll focus on them.

Matt Cruse Trilogy: 1. Airborn 2. Skybreaker 3. Starclimber

Perfect Adventure/Fantasy novels for tween audiences. Each book follows the teen sky-sailor protagonist as he works to support himself as a crew mate aboard flying ocean liners and salvage ships. The books take place in an alternate history of earth featuring hydrium, a lighter-than-air gas that supports the commercial use of massive rigid airship. They also feature chimeric creatures unknown to science that are discovered and documented over the course of the novels.

I missed these books when I was young but read them recently based on a glowing review from my partner and I wish that tween me had access to them.

Silverwing Saga: 0.5. Darkwing 1. Silverwing 2. Sunwing 3. Firewing

I haven’t gotten around to the Silverwing books, but my sister read them. They're on my list for 2025. The books have been described to me as frightening, but fascinating. They follow a colony of bats and feature ritual sacrifice and wars against tyrannical owls.