Ds did Behold and See 5 last year in a coop setting. It was fine. Short, because even though they met only 1x/week, they were finished long before the school year ended, like maybe in February? For us as non-Catholics in a Catholic setting, it was theologically unproblematic, and not too heavy on the God-talk. I mean, I like God-talk, ;) but it's really kinda out of place to have a lot of it in a *science* text. I thought it was quite well balanced in that sense--it mentions God and the wonder of Creation, but not on every page, kwim? The third grade one I have seen extensively and thought pretty silly, in the sense of either "ramp it up some, or just do nature study and call it good". It felt busy-workish to me at that level. However, I have friends who've really liked the B&S3; YMMV, etc. etc. :)