I first discovered hexaflexagons when I was teaching mathematics. I later used the template for making a hexflexagon and used my own art work to put Bible memory verses or Sunday School teaching points on them. Because the hexaflexagons are so interesting to older primary (elementary) aged children I found that they were a great activity to be used in teaching or for a lesson review.
You may be wondering at this point "well what is a hexaflexagon"? They are not easy to explain but the websites below give you some helpful templates and photos so that you get the idea. Once you make one yourself you will see the potential here for using them with children or even creating an evangelistic tool for use with adults or in mission situations. May the 'flex' be with you!