Looks like the herbs resources are pretty well covered. Here's some ideas for the human body - which is a good place to start off the whole topic.
Bones - see if you can get a skeleton somewhere (maybe from Halloween stuff??) for identifying bones.
Outlines - find some large pieces of paper and outline each of the kids and get them to put in body parts that they know - don't show them where they go etc . Do it again after learning about the body and they'll be able to see how well they have improved. This will work for all the ages in the family - fun for adults too
See if you can visit a doctors office or similar to talk about/watch/have a cast put on.
Learn about Leonardo Da Vinci and the amazing things that he learnt/drew about the human body.
I'm sure there are companies that you could send away for free resources on healthy eating etc. Talk about the different ideas that people have as to what is healthy and what isn't.
