Because we're currently homeschooling, we have some curriculum in mind already. The curriculum we're using for theology, history, and literature is the Veritas Omnibus curriculum, which is fairly intense for an adult student, let alone our 6th, 7th, and 8th-graders.
So far this year they've read The Epic of Gilgamesh, the Codes of Moses and Hammurabi, R. C. Sproul's Chosen by God, C. S. Lewis's Till We Have Faces, The Oddyssey, the first five Narnia books, Genesis, Exodus, 1st and 2nd Samuel, 1st and 2nd Kings, and they're currently chewing their way through Histories by Herodotus. I know I left a few things out of the above list; I don't have my reference in front of me at the moment.
Their moms are covering math, science, and other subjects during the day, and we meet for three evening classes per week to cover Omnibus. Much reading and writing and thinking goes on. My daughter complained to me "Daddy, the other stuff we just had to learn. For Omnibus, we have to think!"
That comment satisfied me that we were on the right track.
Zoicks! I get the Veritas catalog, and that's a very intimidating-looking program!
We're more "unschooling," except for math and religion. My oldest (10th grade) is involved in the Complete Works of P.J. O'Rourke, and had the 2 and 4 year old re-enacting the 1991 Gulf War with Lego cars and airplanes. "James! You crashed an airplane on Pat's embassy! That was bad, James!" (James talks to himself.)
Pat (the 4-year-old) read 9th grade Church History, and now he calls everyone heretics if they don't speak Greek.
It seems to be working out reasonably well (aside from having a kid who thinks he's the Ecumenical Patriarch, and also invisible). We use the standardized tests every year to make sure we're not totally off the radar.