This week Bob Lochel wrote about 3 Phrases from Math Class we Need to Expunge, which reminded me of the google doc I started and then forgot about. I wrote about it on here before this blog had a following (does it have one now?). So I tweeted and Bob blogged and now I’m blogging again. With enough repetition perhaps people will remember to add to this document the next time they think of a trick students memorized without learning. Or a vocabulary word students really don’t understand the definition of.

Topics:

**What tricks do you hate when students shout out?
What words do your students use without understanding?
What notation do you wish students started using earlier?**

Please contribute your pet peeves or pet projects. What would you really like to tell all textbook authors/teachers/tutors?

I am myself struggling with figuring out the proper words to use for “cancel out”. I like the suggestion on the google doc of saying “dividing out”, but what would you say for when you add or subtract like terms and they become zero? “Add out” and “subtract out” doesn’t sound like the best option.

@mathcorestandards, I’ve taken to saying “zero out” and “one out” t remind what is actually left behind. And zero out is a totally normal phrase to say, so it works.

Personally, I have cross multiplying.

There are a ton of “trick” kids pick up in elementary and middle school that are best left unsaid. I don’t like the “alligator mouth” for inequality symbols and I NEVER say it, but kids always say it. Anyone have a better way for kids to remember which way the inequality symbol faces? I’ve tried telling them to look at which part of the symbol was smaller/larger.

I also don’t like the “keep-change-flip” and “keep-change-change.” When I first heard these I had no idea what my students (then tutoring) were talking about. I eventually figured it out and now that I’m teaching I tend to just go with it because that was the way they learned. It seems so confusing because they represent two totally different concepts yet are so similar in the way they remember them.