"Miss V., why are there eyes in the ceiling"?, she nervously asked.
The entire class immediately stared up at that missing ceiling tile and, sure enough, three sets of eyes peered back at us. I calmly asked the students if they would slowly get out of their desks and follow me into the hallway. We left, shut the door, and I immediately paged a custodian.
It turns out that a family of raccoons had moved in during summer vacation. They knew they were there, but the exterminators could not find them and said that the noise of the students coming back would likely draw them out. They were right!