MGTutoring.com. A Rational Perspective on Education. » Mathematics

A Student Speaks

Administrator — Mon, 25 Jul 2011 14:13:43 +0000

” ‘Use logic in math’ is my motto.” — Sophia S (October 31, 2010)

That, and persistent, hard work, are why she gets mostly As. I love that quote.

Math Humor

Administrator — Wed, 20 Jul 2011 23:30:44 +0000

HT: Jenny A

Pythagorean Triples

Administrator — Mon, 18 Jul 2011 15:37:01 +0000

Geometry For Enjoyment and Challenge, by Rhoad, Milauskas and Whipple (publishers McDougal Littell/Houghton Mifflin), has some rules for generating Pythagorean triples (see also Mathworld.Wolfram.com) on p. 403:

Rule of Pythagoras: for n an odd number, the triple will be n, (n^2 – 1)/2, (n^2 + 1)/2;

Rule of Plato: for n an even number, the triple will be n, n^2/4 – 1, n^2/4 + 1;

Rule of Euclid: for m and n both even or both odd, the triple will be (m – n)/2, sqrt(mn), (m + n)/;

Rule of Maseres: for m and n any two integers, the triple will be m^2 – n^2, 2mn, m^2 + n^2.

Nice!

The Importance of Mathematics: An Example

Administrator — Tue, 12 Jul 2011 14:22:18 +0000

The Lake Peigneur salt dome drilling disaster, which you can read about on Wikipedia and see on YouTube (and on EducatedEarth.com), demonstrates the importance and truth of the dictum “measure twice before you cut once.”

Mental Math

Administrator — Sun, 03 Jul 2011 13:28:15 +0000

On YouTube, Total Breeze has some good videos on mental math: addition, subtraction, multiplication, division, and square rooting. Worth watching.

Postprandial Math Joke

Administrator — Wed, 29 Jun 2011 22:26:57 +0000

Q: Why do mathematicians, after a dinner at a Chinese restaurant, always insist on taking the leftovers home?
A: Because they know the Chinese remainder theorem!
From Volker Runde’s Math Jokes page.

Beach Math Joke

Administrator — Tue, 28 Jun 2011 14:02:59 +0000

Q: Why do you rarely find mathematicians spending time at the beach?

A: Because they have sine and cosine to get a tan and don’t need the sun!

From Volker Runde’s Math Jokes page.

Math Joke

Administrator — Wed, 22 Jun 2011 02:57:41 +0000

Q: What do you get if you divide the circumference of a jack-o-lantern by its diameter?

A: Pumpkin Pi!

From Volker Runde’s Math Jokes page.

Mistakes in Modern (Public) Education

Administrator — Thu, 16 Jun 2011 16:43:28 +0000

In “Singapore Math Tough to Adopt” (Education Week, Teaching Now Blog, June 9, 2011), Liana Heitin writes:

And Singapore Math requires extensive (and costly) professional development, and “a depth of understanding most U.S. elementary teachers don’t acquire in their math training,” according to [Bill Turque at The Washington Post].

And in “NAEP History Repeats Itself: Flat Scores Except 8th Grade” (Education Week, Education Week Spotlight, June 14, 2011), Erik W. Robelen writes:

The nation’s 8th graders posted gains in American history achievement compared with four years ago, new data show, but only a small minority, 17 percent, were rated “proficient” or higher in the subject.
…
Meanwhile, at the 4th and 12th grades, history essentially repeated itself, with no statistically significant changes since 2006. Just 12 percent of seniors and 20 percent of 4th graders scored at least proficient.
…
“It should concern us all that 12th graders’ knowledge of history has barely changed since 2001,” [said Diane Ravitch, a research professor at New York University]. “All of these students will be voters in a year, and almost 40 percent were already eligible to vote when they took the assessment. … They should be well informed and capable of weighing the contending claims of candidates, especially when the candidates rest their arguments on historical precedent.”

We need to privatize education, and make it rational and objective. These things would help teachers and students alike, in all sorts of ways. Both teachers and students deserve better.

Pendulum Waves

Administrator — Fri, 13 May 2011 02:02:54 +0000

Someone posted a video of pendulum waves on YouTube. Absolutely amazing. Beautiful.