Brown spots on ball python's tail?

[Bogertophis]

...When I get my own snakes I will feed them frozen thawed....

I did confront him about the lack of heating a few months ago, but he said it was warm enough in the school for them (maybe for them not to die, but it is definitely not warm enough!!) and its hard to convince a teacher they're wrong, especially in the middle of class. He also keeps corn snakes, a king snake, and a bull snake in very similar cages. He says he got the cages 30 years ago and the company is now out of business, so he doesn't want them to melt.

Re your plans to feed your own snakes "f/t" in the future- Also for getting involved, to advocate for these unfortunate animals that cannot speak for themselves- Thank you!

If he got these (Neodesha) cages 30 years ago, that tells me that he's been at this a long time, apparently hasn't learned new things, & is very set in his ways. (It sure reminds me of that nature museum I had to deal with.) If his cages are so old they're now a hazard or otherwise unsuitable, then he needs to upgrade & provide enclosures that CAN be heated. That's a lame excuse.