I agree that Outdoor Secrets and the Companion are enough. I am doing OS with my 6 year old this year and we absolutely love it. It’s perfect for little ones just starting to appreciate the magnificence of God’s world.
When we want to learn more about something, we just stop where we are and borrow books from the library on the topic. ***We commonly turn to the Jim Arnosky books available from the library. I would buy every single one if I could. The Arnosky books are just absolutely wonderful. You could simply use those only and have an entire of year of science before you for young ones. I can’t speak highly enough of those.
Ditto using Favorite Poems Old and New and the Comstock Handbook for additional information.
Don’t forget to go on Nature Walks once a week. Those are the best!!!
May the LORD bless you and keep you, Mollie