School that's a rival of 30-Across, informally

UPENN

"Here’s a helpful hint for the clue: "Ivy League school whose name is often shortened to four letters, starting with 'U'." This hint: - Narrows it down to Ivy League schools (a smaller subset). - Mentions the abbreviation format ("four letters, starting with 'U'") without giving away "UPENN." - Avoids repeating the rivalry aspect of the original clue while still guiding the solver."

This crossword clue uses a combination of wordplay and a cultural reference to lead to the answer "UPENN." 1. "School that's a rival of 30-Across" – This indicates that the answer is a university that is a traditional rival of the school referenced in 30-Across.