The holy grail of classical education is the integrated curriculum. What a chalice that would be!
Two things have kept us from finding it. The first is that we've been looking in the wrong place. The second is that there hasn't been an integrating tool.
First, we've been looking in the wrong place. Put simply, I mean that we have been looking at the content of our curriculum in terms of the material we cover. The information, the checklists, the data - if you like.