Monday afternoon found Cornelius and Franny in Room 203 – detention with Mr. Pace. Franny was slumped down in her seat, watching Cornelius fix the smart lamp. If Mr. Harrison had been in charge of their detentions, the smart lamp – or any other inventions – would not have been allowed. But Mr. Pace was the music teacher, and actually liked Cornelius, so he didn't mind. He actually spent most of his time chuckling about the science department getting their comeuppance.

"Cornelius?"

"Yeah?" He was poking a pair of screwdrivers around like lockpicks.

"Thanks."

He looked up, stunned out of his mechanical world. "Of course," he said with a smile. "What are friends for?"

Franny raised an eyebrow. "Well, I know what they're not for. Friends aren't supposed to blow stuff up in each other's faces. Sorry I've been crazy all week."

Cornelius shook his head. "You were worried. And if you hadn't been all crazy, those frogs would have died. You did the right thing." Hesitantly, he took her hand.

She beamed at him, then sighed dramatically. "You won't be saying that next month. We'll both be so sick of detentions that we'll want to time-travel to the end of the school year just to make it stop."

Cornelius grinned. "That's not a bad idea."

30 YEARS LATER

Wilbur Robinson was pleased with himself. He had returned to the present – or "the future" as he thought of it now – with no major mishaps. No paradoxes, no apocalyptic explosions of the space-time continuum. He hadn't even nicked the paint on the time machine. The only thing he had to worry about now was talking his way out of that essay he was supposed to have written for today. But that was child's play.

He strolled into his classroom, prepared to deliver the perfect line –

"Mr. Robinson, you are tardy."

Wilbur did a double-take. Mr. Harrison, thirty years older and madder, was standing behind his teacher's desk. He was wearing the badge they gave to all substitute teachers. Wilbur felt all of his confidence spiral into a space-time continuum vortex.

"How are you still alive?!" he blurted. The man must be 200 by now!

"Mr. Robinson," the owl-faced Mr. Harrison repeated. "I've waited thirty years for this…detention!"

A/N: I'm sure all of his classmates were very confused.