Why does the narrator say that the minutes they spent waiting for the school closing were agonizing?

Answer: Anxiety from Uncertainty

Explanation:

The Narrator described the minutes spent waiting as agonizing due to the uncertainty surrounding the news. As the news bulletin progressed and they did not announced the school closing, the Narrator and their siblings grew more anxious because they were not certain that they wouldn't be going to school which was the news they were waiting to hear.

This feeling was agonizing not unlike how lottery ticket holders feels when watching the lottery.