Rebecca Zook - Math Tutoring Online

Here’s a fun way to remember the formula for surface area of a cylinder—singing these lyrics set to the tune of Camptown Races (in the style of Foghorn Leghorn):

2 times pi times r times h; that’s the middle.
2 times pi times r times r; top and bottom, too.
Surface area!
Of a cylinder! It’s
2 times pi times r times h plus two times pi times r times r.

If you’re not sure about how to fit the lyrics with the Camptown Races melody, just listen to the intro of this sweet rendition on YouTube:

With this handy mneumonic device stuck in my head, I feel the urge to belt “Surface areAAAA! Of a cylinDERRRR!” while walking around my neighborhood and puttering around my kitchen!

Many thanks to Becky Brickell for sharing this great idea on the Texas Instruments Classroom Activities website!

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Growing up, I remember learning to remember the difference between the greater than and less than signs by imagining a hungry alligator with an open mouth getting ready to “eat” the bigger number.

I recently got to work on this concept in an online tutoring session with a student of mine who’s a fifth grader.

First we had a regular < sign and we talked about the "alligator" idea.

He drew in some pointy alligator teeth:

Then he spontaneously drew a whole alligator:

As we worked on different inequality problems, he took it further. He drew a picture of a bird and explained that the bird’s closed little beak is shaped like an inequality sign. The bird would go for the smaller meal, while the alligator would go for the bigger meal.

And he topped it off – with sound effects.

The smaller number, which the bird would eat, has a “peck peck” sound. The larger number, which the alligator would eat, has a “chomp chomp” sound. Oh my gosh, I love it!

I’d never seen the alligator metaphor pushed this far before, and I wanted to share my student’s creative ideas!

What’s your favorite way to remember (or teach) the difference between the two signs?

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Gallon Man to the Rescue!
Five fun ways to help your kids learn math (this summer)

To celebrate 3.14 – PI DAY – here is a beautiful music video of an awesome song about PI !!

It’s a delightful way to learn or remember some important facts about this lovely number, 3.14159….

Here are the lyrics. I would love to know who wrote the song (couldn’t figure it out on google) and who made the gorgeous video (the info was all in Russian).

(Thanks to Sue Van Hattum for posting this on *her* blog today, and to Maria D for sharing it on her Natural Math google group!!)