When I was a kid, maybe around 7 or so, dad, mom, me and sis took a trip to Houston to visit one of dad's buddies.
We were in a '62 Cutlass. Apparently AC was not yet a big thing in automobiles, at least not in cars sold in Indiana where we lived. It was scorching hot as we got closer to our destination. We kept noticing other cars with windows rolled up. WTF? Dad decided that the locals knew something we didn't, so up went our windows!
Yep, you guessed it. The crayons that me and sis were playing with melted. Luckily they were on the floor. I do not recall how soft the crayons got, probably (hopefully) didn't liquefy completely. And thinking about it now, I wonder how many of his perpetual Pall Mall reds dad smoked with family enclosed in that oven of a compact car. Good times.