One of the best ideas I have found so far is the Green Hour Challange, which we will be adding to our Ecojournal days. This was found by going to Mom Is Teaching, which by herself, she has worlds full of great ideas and stories, and most of all, information.
Currently, our homeschool schedule is starting to be a bit full. Next year, with Alex home as well, will be even more full. And trying to find ways to implement studies that fit both children will be a challange... but one I am looking forward to.
The types of studies that Cyan and I are doing now, especially the nature studies, will be easy to add Alex into. And he also needs a refresher in things like phonics and spelling, but that is about where the similarities of the two grades will end.