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Showing posts from September, 2007

I've had some fun building this page about math readers , or "living math" books for my main site. The list is not terribly long yet, but it will grow, I'm sure. I discovered that Amazon has all kinds of new "widgets" available to promote their products. What do you think of this? It is a slideshow featuring MathStart readers by Stuart J. Murphy. Hover your mouse over it: Amazon.com Widgets Math story books offer children an interesting way to learn math concepts, to get interested in mathematics, and to explore some fascinating topics outside of the main curriculum. It is one way to bring math to "life". Kids are almost sure to enjoy it. On my page , I list for example Cryptoclub, a fascinating storybook that teaches how to encrypt and decrypt secrete messages, or The Adventures of Penrose - THE MATHEMATICAL CAT, in which you will encounter many fascinating mathematical topics from fractals to tessellations, or many books for little kids. I wa

### Carnival of math

You might not have heard about it, but there exists a blog carnival for math, too. I submitted my rainbow entry into the latest one. Not all of the entries there are higher math, by the way, such as MathMom's Calculator rant or Puzzler puzzled from JD2718. If interested, go check it out: Carnival of math, edition 17 !

### Humorous short history of mathematics

Enjoy: A Very Short History of Mathematics This is how it starts: MATHEMATICS is very much older than History, which begins* in +1066, as is well known; for the first mathematician of any note was a Greek named Zeno, who was born in -494, just 1,559 years earlier. Zeno is memorable for proving three theorems: (i) that motion is impossible; (ii) that Achilles can never catch the tortoise (he failed to notice that this follows from his first theorem); and (iii) that half the time may be equal to double the time. This was not considered a very good start by the other Greeks, so they turned their attention to Geometry. continue here... Hat Tip to Let's Play Math .

### Tips for teaching integers

The main struggle with integers comes, not with the numbers themselves, but with some of the operations. There seem to be so many little rules to remember (though less than with fractions). Some good real-life MODELS for integers are: - temperature in a thermometer - altitude vs. sea depth - earning money vs. being in debt. When first teaching integer operations, tie them in with one of these models. I'll take for example the temperature. Assuming n is a positive integer, the simple rules governing this situation are: * x + n   means the temperature is x° and RISES by n degrees. * x − n   means the temperature is x° and DROPS by n degrees. It's all about MOVEMENT — moving either "up" or "down" the thermometer n degrees. For example: 6 − 7 means: temperature is first 6° and drops 7 degrees. (-6) − 7 means: temperature is first -6° and drops 7 degrees (it's even colder!). (-2) + 5 means: temperature is first -2° and rises 5 degrees. 4 + 5 means: temperatu

### Number rainbows to learn subtraction facts

I thought some of you (those who teach second grade) might enjoy my NUMBER RAINBOWS. The idea is that you connect two numbers with an arc if they add up to the particular number, such as 13. Then, the child can use it as a reference when subtracting from 13 or when doing subtraction drill. You could first drill subtraction facts WITH the rainbow (such as 13 − 4, 13 − 7 etc.) and then without. You would also ask the child to reproduce the rainbow - and color it, of course! These make for quite pretty math facts practice, don't you think! I'm going to add these to my Add & Subtract 2-A book.

### Prof. Lynn Arthur Steen and reform mathematics

Dave Marain at MathNotations has conducted an online interview with Prof. Steen, one of the principal architects of the original NCTM Standards and one of the most highly respected voices in reform mathematics today. This is how Dave describes the interview: His replies to my questions are thoughtful, honest and provocative. Regardless of whether one agrees or disagrees with Prof. Steen's views, we need to open up this kind of dialog in order to end the Math Wars and move on in the best interests of our children. In this first part of the interview , prof. Steen talks about for example the incoherency of math standards in various states learning basic arithmetic facts.

For those of you who are considering buying my Blue Series books, I've created a document that should help in the "placement". For each of the books about addition, subtraction, multiplication or division I ask you several questions concerning what the child can do or understand. Answering those you should be able to decide where the particular book is needful or not. See more: Math Mammoth placement advice . It does not as of yet contain any tests, but maybe in the future.

### Does the child need to add completing the ten?

Question: ...have an other question about using your worksheets for my daughter. She is six years old - home schooled. Currently, we are using Addition & Subtraction 2 She is able to add and subtract any numbers from 1 to 100 but when I try to explain "complete the ten" concept, she doesn't like thinking about it. She would rather solve 9+6 by counting on the finger 6 after 9 ... . She complains that I have to first subtract then add to make 10. My question is: Should I let her complete the exercises without making her think in this manner? It is important that she understands the IDEA in completing the ten. I gather that she does indeed understand the idea, but doesn't want to do it, since you'd have to both subtract and add, right? She just likes to do one operation, not two? The adding though, is really easy, because you add 10 + 5 or 10 + 7 or something to ten. If she's counting with fingers, she's not yet seeing the easiness of this adding. It

### Review of Flatland: The Movie

The review of Flatland: The Movie has been moved here . (Please update your links, if applicable!)