>>4075919It may sound flippant and I have been called a hack for this talk, but think of your message and think of what pinhole offers. People take their pinhole outside and point it at some random trees or cityscape or their dogs. When they treat it the same as their regular lens, they dismiss it as a toy. If you can change your perspective it may work.
As for a learning tool, why not? It costs nothing to use what you were told - the smallest needle you have and some aluminum foil. Use a pinhole calculator to get close enough. You can skip wasting a lens cap and just wrap the foil around the body to play with it.
https://www.mrpinhole.com/calcpinh.php 