These are pieces I found humorous, and they’re definitely short enough to read in one sitting (or share with students if you’re using the humor writing unit plan from TeachersPayTeachers.)
The Book That I Haven’t Started Writing Yet Will Be the Best Book Ever, by Annabelle Gurwitch in The New Yorker
Cozy Cardigan, cartoon by Roz Chast
The Winter Olympics, Abridged, by Alexandra Petri in The Washington Post
Hey, You Got Something to Eat? by a goat. (Commentary section in the Onion)
If you’re a teacher who would like to teach a humor-writing unit in your classroom, you can find a classroom-ready unit plan on Teachers Pay Teachers.