There was an interesting 4 minutes at Sunday school today. I very briefly introduced Vav and pointed out some of the circled vav's in the pictures here. Then I took a writing implement (a thin point magic marker) and placed the strip on the floor and lightly held the marker against the strip so that I could drag it under the marker making a line as it moved. As I dragged the marker, the children watched the vav's go buy - many of them saying - 'there's a vav', 'there another vav'. Then when the line came back to the starting place - their jaws dropped and their eyes popped out and they said - 'how did you do that?' - and one picked up the strip and looked on both sides of the paper clearly seeing that both had been marked without turning the paper over.
They won't forget the Moebius strip - and I hope they won't forget the vav that connects or hooks words and the curtains of the tabernacle. Not one end to the other with a half-twist, but there are curious connections still to be discovered. There is much more to learn about hooks and they will have fun doing it.
(Incidentally, they can see the differing vowel points, but I haven't introduced them yet. The time will come.)