Across the cafeteria, Ahmed was trying to engage his teammate Mun in a conversation about basketball practice. He stopped when he noticed that Mun wasn't listening. Mun was preoccupied with staring at Rochelle.

Ahmed said, "That's the girl in Health class I told you caused the trouble. Now, what's her name. . . ?"

"Rochelle," Mun said.

"Yeah, right. You know her or something?"

"Something."

"Yeah, well, something was happening to her today. I don't know what her story is but, man, she's weird."

Mun just kept watching Rochelle so Ahmed shrugged and bit into his sandwich. Almost immediately he grimaced as if in intense pain:

"Yaagh!" Ahmed stared at the gray matter between the layers of bread. "What is this stuff?"

"Attention, students!" Mr. Sanchez announced. "Remember to separate paper from plastic in the respective receptacles by the exits! I repeat: do not mix paper and plastic!"