Tuesday, January 5, 2010

My dear Aunt Sally


Imagine: Kansas City Library Central Library parking structure.


When teaching math or science, it is always helpful to have mnemonics. They are wonderful little tools that last a lifetime!!

I grew up knowing that any smart student would "please excuse my dear Aunt Sally". I never knew what my dear Aunt Sally did... but it must have been a doozy. Everyone in my class knew to excuse her. But the funny thing is my school (an Argentine school) taught math in both English and Spanish and we never learned the Spanish mnemonic for the math operations...  I wonder if there was one?

Parenthesis, exponents, multiply, divide, add, subtract - from left to right, in order of operation. Miss Cleary did not let us proceed to any adding or subtracting until we had cleared out all the multiplying and dividing. She was one tough teacher. I loved spanish math much better, though. You did everything in your head. Dividing was written out exactly backwards than the english version... and you did any remainder subtraction in your head, never showing your work. I always thought of it as being less demonstrative, more internal. It was the same as internalizing your thoughts, but here you were internalizing your math.

When I started teaching bilingual Algebra, none of my students had met my dear Aunt Sally. The day I introduced this mnemonic to them, several of them stared at the classroom door as if Aunt Sally would dramatically enter, her chiffon robes flowing and her perfume encasing us all. I had a terrible time keeping my students' attention. It would have been worth having the principal's secretary sweep into the classroom...

But once the students caught on to these four/six english words as the math order of operations, they laughed and bounced in their desk seats. They suddenly OWNED the order of operations!!! They knew Aunt Sally and would never forget her.

If their classmate did not grasp the vision, they helped. The students grew animated and insistent that math problems were solved by 'please excusing my dear Aunt Sally'. The students invented their own game: they asked me for the hardest math problem I could think that included all six operations in any order. Each student had the same problem. Each student would solve the first step, pass their paper to their left, and do the next step - and pass the paper to the left. That meant if your seatmate did the wrong operation, you explained it to him/her and corrected it. These kids love being right!


My students challenged me to any other mnemonics I knew. My brain went blank. All I could remember were science related ones.
King Phillip cried out for green spinach (Kingdom, phylum, class, order, family, genus, species).
My very educated mother just served us new potatoes (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Neptune, Pluto). Oh, wait - Pluto is gone. Sigh... How about this:  My very educated mother just served us nachos??

You can reach a student's imagination just using your own.

6 comments:

Anonymous said...

Teacher, ooo, ooo, Teacher, over here. So tell me what I did wrong. Here's the issue:

Warren is 75, didn't have sex until he was 14, then had it every day of his life, eight hours a day.

So I thought: ((75-14)x365))x8

But that's wrong?

Anonymous said...

(Wrong in so many ways.)

Brenda's Arizona said...

Darn, I thought there was an exponent in there somewhere, Karin. Maybe we better pass our papers to the left and let the next kid figure it out...

Brenda's Arizona said...

P.S. - anyone who has not caught Altadena Hiker's post that references math, go here:
http://altadenahiker.blogspot.com/2010/01/i-heart-journalism.html
- and stand back!

Anonymous said...

I could never remember anything with mnemonics. I used to write the answers on my hand.

Dog_geek said...

Hmmm.. we were taught that King Phillip Came Over From Germany Stoned. Maybe we should be excusing him instead of aunt Sally?