Confusing Bible Readings and Greek Myths

I think that’s a really good idea, to completely separate the Bible from the secular history, doing the secular history as a chunk together at another time. My kids are a similar age to yours. We really don’t want our kids mixing up the histories!!! I had similar concerns as we are about to start with the first SCM volume, the one that includes Egypt. I think we’re planning to skim over the secular history a bit, although I think SCM does a really good job of keeping the mythology and false god stuff to a minimum and in its place.
For another idea, perhaps using a map pin board or similar, and identifying with a mark or a flag or whatever, which country it is you are studying for each lesson (like SCM suggests for later volumes when switching between American and world histories during a week of study)…
What about some simple comparative tables for the children to fill in, for certain topic headings, contrasting Bible history to secular history… or maybe just have them write a paragraph about the major things happening in the Bible versus in the Greek empire during that time period… Just to give them an appreciation for the difference. I do remember doing such a thing for myself in high school learning about European history…
I hope what I’ve written makes some sense!
All the best with your studies!!