Confused Classes

[Ryth]

I recently remembered about something that happened to me last school year. My school has alternating schedules to fit all the specials in the week (Gym, art, chorus, etc.) with Fridays always being different. It was Friday, and I was late, I think I came from a dentist's appointment, and I thought it was an A day (schedule 1), so I went to period one, gym, and I stayed there the entire period, not knowing it was the wrong class (since class started already and all classes were outside, I didn't exactly notice it was the wrong class, nor did my teacher realise I was in the wrong class, which seemed to convince me more it was an A day), I didn't notice I was in the wrong class until after class where I realised I didn't recognize anyone in the locker room. I thought it was funny. xD

So for the topic, has anyone experienced a similar situation, being in the wrong place or something, in school or not?