The curtain of sleep parts ever so slightly and lets in a little light.
“Oh,” you think, “It is time to get up!” you think. “One more day and then the three-day weekend.”
Then a little more light, just a fraction more, and with it, realization: “No, today is Saturday, and this is the three-day weekend, and school is over, and there remain only three teacher work days, and then the summer really and truly begins.”
And the curtain falls again, the light fades, and you go back to sleep.