Visible crew/equipment: After Mr. Feeny says "You are the graduating class of the year 2000," he turns around in front of the back wall. As he turns around, there is a shadow of possibly a boom mic on the back wall which moves as Mr. Feeny moves. (00:04:15)
Santa's Little Helper - S1-E10
Visible crew/equipment: After the bell rings and Mr Feeny says "Have a wonderful vacation," a boom mic can be seen dropping from the top left of the screen as the students are rushing out of the classroom. (00:17:20)
Answer: I learned the answer to this one today. It is "Tree of Life" by Garé Barks.
Phaneron ★