Anecdotal but an example of the burden of being a science teacher and knowing better. ;)
A neighbor boy was all excited to show me his magnifying glass, a little
plastic thing he probably got in a goody bag. “Look Bree, if I look at the sun
it burns a bit!”
You can probably imagine how loudly I shouted “Nooooo!” He was persistent
and I had to actively block his eye and the magnifying glass from the sun for a
while with my own shadow. I tried to direct him to looking at things on the ground with the
magnifying glass. I had him hold the magnifying glass at arm’s length to view
another neighbor. “He’s upside down!?”
He continued to play with it for quite a while, and my science-oriented
heart swelled a bit, when he conducted some side experiments with a translucent
cup on the ground.
“Look, the shadow is green like the cup! If I tilt the cup the shadow
changes. If I move the magnifying glass the little sun changes.”
Out of respect for my friendship with his mother I did not teach him about
the heat at the focus of the magnifying glass. Although when he briefly aimed
it skyward again I was tempted.
The next time we got together I brought home some of my eclipse viewing
glasses. I told all the neighbors (there are nine under the age of ten within a
few houses) that they were the only
safe way to view the sun. Their response was less than impressed, “Oh, it looks
like an orange ball.” Then they tried to see if they could ride their bikes or
walk or play tag while wearing them. Hey, everyday can’t be a victory.