She didn’t mean it, but the word lodged in Sheldon’s brain like a splinter. He didn’t cheat. But he did something worse. He lied.

“You look like a constipated chipmunk,” she said.

Sheldon turned to him, eyes wet. “That’s like saying the Sistine Chapel is just a ceiling.”

The next day, Sheldon walked into school carrying the HP-35 in a custom foam-lined case he had constructed from a shoebox and dish sponges. He found Jeremy at the water fountain.

The trouble began, as it often did in the Cooper household, with a lack of Fibonacci.