"That'd be helpful, yeah. How long will it take?"

"Give me tonight and tomorrow to get it together." 

"Cool. I like it when things are easy like that."

"Anything else you wanted to do before we go?"

"Not unless Stiles has any questions for me...?"

"How do you get your hair like that?"

Pascale leans in close and whispers solemnly in his ear, "Magic."

"If that's everything, we should go." 

"Okay. Bye, Stiles!"

"Bye. Try not to enjoy yourself too much while I'm gone."

Scott drives her home.

"So, anything exciting happen when you left me behind?"

"Not really, just Stiles. Meet your new substitute teacher."

Pascale smiles cheerily at Isaac.

"Starting the day after tomorrow!"

"What subject?"

"I think subs usually can do a couple of things. Pascale, what's your first choice?"

"Math would be easiest, the concepts are mostly the same, just have to translate the symbols. I don't think I could convincingly fake music, much as I'd like to. Geography or history would be okay. I should probably stay away from the sciences, you're too far ahead of what I'm used to."

"History would be okay for a little bit, but you might miss something obvious...math is probably easier, you should do a review of high school level math to make sure it looks familiar. My textbooks are upstairs, we can look at them now."

"Sure, let's go."

So he shows her. 

Nothing beyond differentiation!

If she understands basic calculus, she should be fine. 

The framing of the logic is in slightly different terms, but it's simple enough to grasp. Rates of changes that are themselves changing. It helps that her visualization abilities are better than most.

"I think you're better at math than me, which is really above and beyond for a substitute teacher. I hope Stiles doesn't do anything too illegal."

"Isn't he the son of the sheriff?"

"Yeah, but I don't think he'll tell him anything about you." 

"The sheriff already knows about me, he was at the church when I met your mom."