Math Teachers at Play: Three-Cubed Edition
Welcome to the Blog Carnival:
Math Teachers at Play!
Twenty-seven is one of my favorite numbers, so I was excited to find that “my” edition of the carnival would be number 27.
Some fun facts via Wikipedia (click the link for even more):
- 27 is a perfect cube: 3³ = 3 × 3 × 3 = 27.
- 27 can also be written as 23 using the notation of tetration, which means that it is 3 taken to the power of itself, 2 times:
- a exponentiated by itself, n times.
- 27 is the twenty-eighth (and twenty-ninth) digit in π. (3.141592653589793238462643383279…). If you start counting with 0 it is considered one of few Self-Locating strings in pi.
- 27 is the first composite number not evenly divisible by any of its digits.
I don’t know what I was thinking, agreeing to do a blog carnival in the middle of June! So please accept my apologies for the tardiness of this post, and the lack of creativity in presenting the posts!
Without further ado, the posts:
I always love the way Denise at Let’s Play Math! makes word problems fun by her choices of literary themes, as well as providing excellent explanations of to approach them. Hobbit Math: Elementary Problem Solving 5th Grade is a fantastic example of her wonderful style.
Imagine discussing the Fundamental Theorem of Calculus to a very gifted eight-year-old. Sue VanHattum provides a peek into her work with Artemis in Sneaking Up On the Fundamental Theorem of Calculus at Math Mama Writes….
What happens to the American flag if Puerto Rico becomes the 51st state? Read A mathematician figures out the best way to jam an extra star onto the American flag by Chris Wilson at Slate Magazine to find out! There’s also a fun widget provided so you can see what the flag might look like with an arbitrary number of stars, using a variety of different types of pattern.
David Ginsburg tackles a huge pet peeve of mine — the lack of “sanity checking” of answers among math students — in Estimation Before Computation at Coach G’s Teaching Tips. (I posted a related rant — my Calculator Rant here a few years ago.)
Teachers stuck with silly word problems provided in the officially sanctioned textbooks will appreciate the ideas in One word problem – many word problems at CTK Insights. (This expands on a related post from Dan Meyer a few months back on his blog dy/dan.)
Tracy Beach presents New Teacher Downloadable: Give Parents Ideas to Avoid the “Summer Slide” posted at Math Learning, Fun & Education Blog : Dreambox Learning. (Note that the handout also contains an advertisement encouraging parents to purchase a subscription to their website. I don’t know enough about their subscription service to offer an opinion as to quality or value.)
C heck out Guillermo P. Bautista Jr.’s presentation of Rational and Irrational Numbers at Mathematics and Multimedia for clear explanations and diagrams illustrating that the real numbers are divided into rationals and irrationals.
Shana Donohue presents two zero-based posts at her appropriately-named blog The ZeroSum Ruler: To the Zero! [power] and Dividing by Zero Blows up the Universe!. The middle school students I work with seem to think that the rules about zero are mostly arbitrary. (I kind of agree with them on 0! — 1 is the value that makes all the combinatorial formulas work out cleanly, but I’ve never heard an actual good argument for it otherwise.) But these posts show why and how the rules make perfect sense when it comes to division by zero and raising numbers to the zeroth power! The “to the zero” lesson also extends gracefully into explaining how negative exponents work, and showing that they just keep following the same pattern. :)
Pat Ballew stumps his pre-calc students by asking the simple question, “Given two points, write the equation of a line containing the two points,” in Given Two Points???? at Pat’sBlog. Why are these bright honors students stumped? Because the points given are in three dimensions rather than two!
At the intersection of Math and Computer Science, John Cook talks about what goes wrong when computations with large numbers must be carried out on computers with limited precision in What’s so hard about finding a hypotenuse? posted at The Endeavour.
I missed tagging an incoming carnival post, so this one got accidentally overlooked when I put it together. So now you get an extra bonus post:
John Golden presents a great game to practice ordering decimals in Decimal Point Pickle at Math Hombre. It’s too late for this school year, but I’ll have to bookmark it for next year. Thanks John and sorry for forgetting your submission in my original post!