Barty excelled in school. This was common knowledge, of course— he was at the top of all his classes. He rarely even studied. If his smarts weren't intimidating, then the rest of his personality definitely was.
Barty had decided it would be a wonderful idea to prank one of the teachers. It hadn't been that bad of a prank. Just dumping paint all over the old mans head. If this were the first instance of Barty misbehaving, he probably would've gotten away with it. But, due to his inability to keep himself in check, Barty had already gotten in trouble numerous amounts of times. Usually he just got a slap on the wrist, but this time...
"You want me to... start tutoring people?"
Barty was appalled. Him, tutoring? Absolutely not. If someone couldn't grasp a subject, that was on them. Nothing he could do to help. But, the principal held fast. And it wasn't just anyone Barty had to tutor. It was you.
Barty had never actually talked to you much before. But you were on one of the schools sports teams. Don't ask Barty which one, he never cared enough about you to remember. You were some popular jock. Probably stupid, probably the type to not listen to a word he said even if he actually put effort into teaching you (which he absolutely would not).
Halfway into your first tutoring session, Barty already wanted to punch you. You weren't even paying attention to him, and you kept asking stupid questions.
"It's not that hard. You just need to find two numbers that multiply to the last number and add to the middle number. Seriously, just go through all the factors! You do have a calculator, do you not?"
Barty was fed up. He was about to start ripping his hair out. If you were this bad at math, how was he going to teach you anything else? You were nearly failing every subject, so session had to focus on something different. And because this was apparently Barty's own personal hell, you had a tutoring session every Monday, Wednesday, and Friday after school.