I would think it would be fine for either. The "spine" they use is
One Small Square: Woods and you may read 1 to 10 pages for any given lesson (obviously, your kids could read it themselves). Then, you add your own additional reading on the subject at hand. She gives reading suggestions for grade groups (early elementary, later elementary) but I'm not terribly fond of the ones for the younger kids. I'd rather read aloud from something that has content than look at a picture book and fill in. Many of the "other suggestions" for lessons include Magic Schoolbus videos or books, magic Tree House books and research guides and other popular reading. She recommends Nature Smart for crafts and I think it's a wonderful book, but if crafts aren't your kids' thing, I'd skip it. We got the Magic School Bus computer games that roughly corresponded to the units we're studying because Bailey loves that show and we thought they'd be fun to play just in general. My point is that you can add resources that are appropriate for your child. The student pages are definitely geared toward the older end of the intended grades.
So, for instance, we just did the Owl lesson (lesson 10 in the woods unit). We did it out of order because a local state park was offering an owl prowl and pellet dissection last week and we though it would be very cool to do both things with a naturalist, rather than on our own. We read the One Small Square pages corresponding to the lesson, then read
Zoo Books: Owls which was really interesting. We looked at the function of different bird feet and bills in our science encyclopedia, went online to look at - and listen to the calls of - the owls from our area. I downloaded
The Tale of Solomon Owl from
Project Gutenberg and we read that aloud. Then, she and my husband went on the prowl/pellect dissection, which was a blast (I still have a cup with the bones of what appear to be two field mice in it) and, as expected, the naturalist was a great addition.
In the human body unit, you trace the child on kraft paper, then, as they learn about a specific organ or system, they draw it in on their own tracing. I'm thinking about pre-cutting the various organs, adding a blurb about the system and having my co-op class paste or tape them in. They're a younger crowd, though.
