Play-ful: Adjective: per Merriam-Webster, frolicsome or sportive; humorous or jocular
Play: Verb. A very old verb, dating from the 13th century.
I've been blogging about some serious topics lately. In this post at annarbor.com, Kass (Pioneer High School teacher and advisor to the Neutral Zone poetry collaborative) makes the point that playfulness in teaching goes a long way. [And he also tells you about an interesting upcoming poetry event, Monday evening November 28th at the Neutral Zone.]
He's right! Playfulness in blogging probably goes a long way too, so here is the knock knock joke my nephew told me the other day:
Nephew: Knock knock
Me: Who's there?
Nephew: You are there!
Comment of my niece, who texted me the whole thing: I don't get it either.