In case you've never come across these explainer videos:
http://www.commoncraft.com/videolistTheir trademark is these animations where you can see the hands.
But doing it is quite convoluted; you need good light boxes so your hand's shadow is soft, editing is hard, and printing the assets is not ideal.
I can imagine there's software for this; trying libreoffice impress, pencil, and tupi. Ideally linux based, but if the best is windows-only I can use a win box.