I can see bringing the snake to class, I can't see leaving it there, even over night.

The cleaning crew has been on my mind too. Heck, I've been in buildings when they decided to poison the place DURING work hours. "We're getting rid of mold!" My eyes started watering, I nearly lost my lunch...

That said, we had an excellent science teacher in elementary school. His special interest was Monarch butterflies. He brought in some branches with the actual chrysalises, and we watched them develop. Very memorable. Back a few years ago, when I raised silk worms, I was gathering mulberry leaves from my neighbor's trees while she was telling me her memories of a science teacher who brought silk worms to class.

It does make a difference.