SCM history & sotw

Has anyone combined sotw with scm?  I was thinking about continuing our sotw series, we are halfway with vol 1, and adding in scm history starting with vol 4.  This would allow us to study American history alongside the four year cycle.  We wouldn’t need to coordinate the time period, so it would just be separate.  Would that be confusing for kids?  Too much?  I just would love to study American while kids are young, but I love getting a good feel for all of history too.  I also thought about Notgrass our star spangled story for super easy (except I prefer no textbooks).

My kids ages are 1,4,7,7,9 (pre-K, 2nd, 4th)