X-rays and related discoveries

So this morning the kids woke up all excited to play some math games we had talked about last night, but we got a little side tracked over breakfast which delayed our plans. One of the kids asked while watching one of the dogs beg, "How do dogs wag their tails?" So after breakfast we got on the computer and looked up dog x-rays. We found pictures which explained the original question in addition to a bunch of X-rays showing that dogs will eat some crazy things!

Then Ian said, "Can we see some human x-rays?" which led us to learn the name and placement of many bones and the kids trying to feel those bones on themselves. Then we came across a X-ray of a stomach, which was glowing because the doctors had the patient swallow barium. The kids were amazed by this and asked what Barium is. Then with my limited memory of chemistry I tried to explain that it is an element ( to which the kids said "like the element of surprise?") I laughed and pulled up a periodic table of elements, which I never would have imagined would interest 7 year olds. On that page there were pictures of kids baking cookies and decorating them to create a periodic table with one cookie per element... guess that will be a project today or over the weekend!!