The other day, my wife and oldest son were having an intense debate over the importance of flash cards.

She was of the opinion that he should be creating flashcards for his upcoming science vocabulary test.

He thought she was crazy. After all, he already knew all there was to know. What was the point of flashcards?

Naturally, they turned to me to solve their disagreement.

“Um,” I said, hesitating. On the one hand, I’ve never been one to make lots of flashcards. On the other, my wife would most likely break my knees if I didn’t back her up. Okay, not really.

“Here’s the deal,” she said. “I’ll ask you these. Any you don’t know, you have to make flashcards for.”

“But most of them are self-explanatory,” he said. “That doesn’t make any sense!”

“Self-explanatory?” I said.

“Yes! Like crust!”

“How about lithosphere?” I asked, having heard that particular term earlier in their disagreement.

He threw his arms up. “Self-explanatory!”

My wife gave me her well-earned “see what I’ve been dealing with” look.

I smiled at my son. “I don’t know if that one’s self-explanatory.”

“Yes it is!”

“So… then… what’s a litho? I mean, I get the sphere part, but what’s a litho?”

“Aaaahhh!!!”