Cecily's classroom was less a classroom than it was an Ancient Greek forum, carved of marble shortly after the Bronze Age. Very little had changed here since then - though she'd tried to donate the entire thing to a museum once, no one wanted to set one up on an island so far from mainland Greece that the only way to get there was a day's boat ride from Crete.
The forum had no walls, instead having a circle of carved marble columns stretching twenty or so feet up, supporting a stone dome that served as a roof. You could do things like that when you were the most powerful witch in Greek antiquity. No matter how hot or cold it was outside, the inside was a constant sixty-eight degrees.
Only a handful of new additions had been made here since this place's creation: the first an enchanted blackboard one of Cecily's ancestors had put up sometime in the 18th century. She had no intention of replacing it, not when it cleaned itself and could write on itself without her touching it. It was currently clean apart from the words "Transformation 101" in block print in the center. The others were a large stone arch, covered in carved runes, that was used for summoning and a sphere in the center of the dome that powered any electric objects in the forum. She was proud of that last one - that had been her creation.
The stone arch glowed, reminding Cecily of the time. She could see reality tear itself in two inside the arch as a portal opened up, the first of many. When you were in the middle of the ocean, you couldn't exactly use a school bus to get your students here. Each of them had found a flyer she'd printed out and enchanted by hand, visible only to those interested in the art of transformation, which would open a portal to her classroom at a specified time. Whether they took it or not was entirely up to them.
She waited a few minutes for any stragglers, until the stone arch stopped glowing and reality established itself once more.
Cecily stood from her chair, hoping that she'd be recognizable as a teacher. At five foot eight and wearing nothing more than a college hoodie and jeans, she didn't exactly cut the same imposing figure the previous occupants of the island had. "Welcome, everyone. Please, take a seat. My name is Cecily, and I am the tenth descendant of the witch Circe, despite not having a blood relation to her. This is Transformation 101."
A few of the students stared back at her like she had three heads. She was used to that.
"If any of you wish to leave, simply walk back to the stone archway and I will send you back to your home. For those of you who choose to stay, I will teach you the art of transformation. Even if you have no magical background.. and given the current state of the world, I expect most of you do not.. by the time you leave here, you will be at least competent enough at the art to teach yourself the rest."
Not a single one of the students went back to the arch. They almost never did.
"I expect, given that only those with certain interests can see the invitations you've all received, that many of you know who the witch Circe was. If not.."
The chalk on the blackboard began levitating by itself, as the words "Transformation 101" disappeared off it. By itself, the chalk wrote "The Witch Circe" on the left side of the board, taking notes based off Cecily's dictation.
"Circe was, at one time, the most feared witch in all of Greece, if not all the world. You may have seen one of a number of paintings of her transforming an entire boat of men into pigs.. her most famous feat. At the height of her power, Circe was practically a demi-god..."
The chalk continued taking notes. All eyes were on it. If her students hadn't been aware of magic, they were in for a shock.
"...until the fall of Greece to the Romans. Long story short, she lost her bid at godhood and decided to curse the world so that there'd always be a Circe. That's why I'm here, and not working a regular teaching job."
The chalk stopped, then wrote "Rules" on the other side of the chalkboard.
"I only have two rules for all of you. The first: never attempt to use what I'm going to give you on anyone else without their express consent. I set up my classes specifically so that you will never gain the ability to transform others, but if you somehow do... just know there are higher powers than me out there who will not appreciate it. The second: there's no shame here. That's a concept for ordinary people, and none of you will be ordinary people by the time you've finished my class."
Cecily smiled. "That's the boring stuff out of the way. And now, I need a volunteer. Just raise your hand."