Wee Folk Art as core

I have 5 kids (6, 5, 4, 4, and 2 tagging along). I am looking for plans for next year when I will have 2nd grade, 1st grade and 2 pre-k. I really like the idea of the Wee Folk Art curriculum. Does anyone use it? I love how it has nature topics, some crafts (though those probably wouldn’t always happen!) along with poetry/music/art. I was thinking of using Wee Folk Art as a “core” for science/nature, poetry, art and music for all of my kids. DS6 will need some additional supplementation with harder books to read independently I think. Has anyone used this? Thoughts? Here is the website: 

http://weefolkart.com/content/homeschool-companion-guides