We recently discovered the National Audubon First Field Guides series. M has been enjoying looking through the pictures of the field guides we own for some time and these shorter guides for kids have been a real hit. She enjoys looking at the pictures on her own and listening to me read the sections she is interested in. I can imagine using them for lots of science lessons in the future.
So far, we’ve checked out the guide on shells, wildflowers, rocks and minerals, and birds. Unfortunately most of them are out of print but they are easy to find used or your library may have them.

[...] Picture Book of the Day (Perfect Timing) 2. Sarah (First Field Guides) 3. Cloudscome (Psalms for Young Children) 4. Laura Salas (Cave) 5. Sara Lewis Holmes (Request [...]
We love Audobon books, any of them!! We’ll look for these first field guides, they look perfect for a backpack