I would be hesitant to try and homeschool foster children, unless that's what they were doing prior. It's so hard for these kids with so many transitions, that I would avoid any major changes that can be controlled.
I homeschool my younger son, so am a huge proponent - but think it should be saved for children you will have forever. In addition, while its vastly superior to most of the public school system, many foster kids will bring baggage from their life experiences, and you may find it hard to be with them 24/7. School may give everyone a much needed break.
All of that said, sounds like it may be a ways away.