Kristina....what do you mean social studies?
Are you wanting some history some geography, a little of both.
I know social studies is probably the political correct term used nowdays in schools. Its meaning is pretty broad. I really don't like it
I personally like doing history following The Well Trained Mind where you study period or chunks starting with the ancients and working your way forward to modern. The beauty of this is that you can do both kids at the same time.
However, I can't remember you state's law. Do you need something in a spiral fashion...i.e. like public school where you cover basically a lot of time periods in one year, with the idea being that you will build each year on them OR are you free to choose?
Let me know so maybe we can get you going in the right direction