I almost do 🙂 I started out trying different things, but as the years have continued I have settled into many SCM materials and been very happy with the results.
History – SCM History Guides
Geography – SCM Visits to… series
Language Arts – SCM Using Language Well and Spelling Wisdom (along with oral and written narrations)
We also use SCM poetry guides, hymn study, picture study portfolios, Composure study. Oh and Delightful Reading level 2 for my youngest.
The only place we really branch out are for math (Math U See), and Apologia for science. The new SCM science guides for elementary look really good, but we enjoy Apologia and it is nice to have just one book for science with so many other books for other subjects.