I am trying to prepare a "mathematics talk" for five year olds from my daughter's elementary school. I have given many mathematics talks in my life but this one feels very tough to prepare. Could the members of the community share their experience with these kind of lectures. I was thinking to talk about some theorems of Euclidean geometry which will include some old fashion compass, straight edge construction with some kind "magical outcome" and then try to give kids some logical reasons for the "magic". Any ideas?