Julia,
We have used both SCM and FIAR, differing years. I use CM methods with both: oral narrations, copywork, map work, living books, read alouds. We add in extras like artist and composer studies, poetry, etc. with both. The difference I see is in which type of living books you are using and when.
FIAR is unit studies so all your science, history, geography, language arts, art, etc. lessons all tie into the focused picture book. It is for elementary level only. You still use living books and CM methods for studying those books.
SCM studies unrelated topics. You choose an area of science to study for a whole term. Add in nature study. You study history chronologically. Your art lessons or handicrafts do not necessarily tie into any other books you are reading. But again you are using living books with CM methods.
We have enjoyed both. Both can be done as a family. You can add whatever you like to any curriculum you choose and make it fit your family. You can skip some of their books and substitute with your own. By familiarizing yourself with CM methods, you can apply them to whichever books you like, though CM did not use unit studies. It depends on how closely you want to adhere to her philosophy. You are educating a whole person: academics, character, Bible, habits, & life skills. “Education is an atmosphere, a discipline, a life.” – CM Enjoy the journey!
