What day is it?

I've always said teaching is a constant uphill battle. You know the odds are against you when the following happens:

This story is 100% absolutely and completely true. Here's the set up...

One of my students was absent on Monday. On Tuesday he returned to school. As any teacher does, I welcomed him back, told him we missed him, and inquired about the reason for his absence.

Me: Hey, Johnny! Welcome back! We missed you yesterday! Is everything okay?

Johnny: Yes.

Me: Were you sick yesterday?

Johnny: No.

Me: Well, where were you then?

Johnny: At home.

Me: At home? Goodness! I hope everything's alright.

Johnny: It is.

Me: So, why were you absent?

Johnny: Because it was Sunday.

Me: Sunday? Ummm... No. Yesterday was MONDAY.

Johnny: It was?

Me: Yes. It was.

Johnny: Oh. I thought it was Sunday.

Me: (walks away speechless and shaking my head).