I've written here about liking an immersion-type thing with environmental books, books that don't wear a sign saying "It's eco-time" but just make readers part of a natural world or lifestyle. Maybe what I'm thinking of is some kind of wholistic experience.
That's what I think happens with Mouse and Mole: Fine Feathered Friends by Wong Herbert Yee. The book has a Frog and Toad vibe, which is good, though wordier. Fine Feathered Friends is all about Mouse and Mole watching birds. And drawing them. And writing poetry about them. The whole thing.
Over the course of a story about the two friends having to find a way to get close to the birds they want to draw, Mouse and Mole pass off a small amount of avian info. But what really makes this book at all environmental is that Mouse and Mole want to do this bird stuff. They want to draw them and write about them. They want to have a life that involves birds.
Listen, when I had little kids, I would have read them this book, got out their artists' journals (yeah, we all had artists' journals), and gone out with them to find us some birds. It would have worked as an environmental book for me.