I've been teaching my students about adding and subtracting integers. It's always tricky to learn that when you subtract a negative, it's actually just the same as adding a positive. That is, for example, 5-(-2) is the same as 5+2, or 7.

And when most of us learned it, our math teachers told us it was just like English class. I tried the same illustration...

"It's just like English class, guys. If you use a double negative in English, it actually means a positive. Like, if you say, 'I don't got no pencil,' that actually means you DO have a pencil."

I knew right as I was saying it that it would never work. Sure enough, one girl immediately interjected... "Whachoo mean, mister?! No it don't! I talk like that all the time!"

And when I gave the example to my ESOL kids, the ones still learning English, I remembered back to my high school Spanish days, where we learned that when speaking Spanish, often you DO use double negatives.

Time to find a new illustration.