Tuesday, December 30, 2014
Tuesday, December 23, 2014
The Chopsticks Problem
Solution:
We can make any number of triangles from 1 up to 10. There are multiple solutions for each number. For examples, click here.
Tuesday, December 16, 2014
Tuesday, December 9, 2014
Wednesday, December 3, 2014
Tuesday, November 25, 2014
Wednesday, November 19, 2014
Thursday, November 13, 2014
Wednesday, November 5, 2014
Wednesday, October 29, 2014
Wednesday, October 22, 2014
Wednesday, October 15, 2014
Thursday, October 9, 2014
Wednesday, October 1, 2014
Monday, September 22, 2014
Special Blog Carnival Edition of 1001 Math Problems !
Welcome to the 78th edition of the Math Teachers At Play math education blog carnival, which I am thrilled to be hosting this month in celebration of my soontobereleased book, Camp Logic. What is the blog carnival? It is a monthly snapshot of some interesting recent ideas and activities posted by math education bloggers all over the internet.
For more information about the MTaP blog carnival, including previous editions, click here.
By tradition, I begin with a fun fact about the number 78....
Seventyeight is the 12th triangle number, which means that it is the sum of the integers from 1 to 12. Therefore, it is also the total number of gifts given on the last day in the song "The Twelve Days of Christmas!" Here's a visual:
And speaking of triangle numbers.... Of course, we don't need to stop with triangles. We can generate polygonal numbers for any ksided polygon, and blogger Guillermo Bautista shows us a clever method for finding a general formula for the kth polygonal number.
In his blog, "Curious Cat," (a blog about engineering and science) John Hunter gives us a wonderful example of how our intuition can lead us astray and how a little math understanding can help you see things more accurately and more clearly. This is in the same genre as the classic Monty Hall Problem.
Mike Lawler shared this Three Chips Problem from Fawn Nguyen, which is superficially a simple problem about sums of singledigit numbers, but the problem quickly draws kids into reasoning about arithmetic sequences, combinations, and systems of equations. This is characteristic of my favorite sorts of problems: easy to state and challenging to solve. Very cool.
Denise Gaskins, in her blog, "Let's Play Math!", gives us another example of such a problem (easy to state, challenging to solve). A simple question about sharing sausages leads to insights about adding fractions and about common denominators, even before children are introduced to these concepts in a formal way. The blog post is also valuable for what it says about pedagogy: that children need plenty of time to explore and to think, and often the best thing that a teacher can do is simply to help students to clarify their own ideas by asking them questions.
Maria Droujkova's blog, "Moebius Noodles," includes an interview with the fascinating Dr. Melissa Kibbe, a cognitive psychologist who studies mathematical thinking in young children. She is interested in particular in how our experiences and the early "gutsense of number" that we build through those experiences impact our formal understanding of mathematics later on.
More posts about elementary math education:
Malke Rosenfeld is a selfdescribed percussive dance teaching artist and math explorer (among other things). True to her background, Malke finds ways to combine math and movement. In this blog post, John Golden, the Math Hombre, discusses and endorses Malke's Clap Hands game.
Dan MacKinnon blogs about simple origami projects on his "Math Recreation" blog. Origami is a wonderful math activity for many reasons. Even the simplest origami gives students builds students' intuition about mental rotations and reflections, gives them practice with learning to read diagrams, and builds persistence. (It takes a lot of persistence!) While it is easy to find books of origami projects, it is not so easy to find simple examples for beginners, and MacKinnon's blog post is a perfect start.
On her blog, "The Kid's Quadrant," Amy Tanner gives us the idea of a "quantity" scavenger hunt to help accustom children to seeing quantity as an attribute in the world around them. I imagine that this exercise is also great for having children build a mental "catalog" of visual images that will also help them visualize arithmetic. A child who "sees" the fourness in a chair can then easily "see" 16 as four chairs around a table. Just a thought.
Jennifer Baselice ("LOL with Technology") blogs about thinglink.com, and how she used the website to create a digital platform for her students to collect and display examples of different mathematical concepts.
Margo Gentile ("Margo's Math and More") gives us an idea for using the resizing function on Power Point to help build kids' intuition about scaling and similar figures.
More posts about middle school / high school math education:
Mrs. E. (Kerrie Everett) details a project she does at the end of a unit on similarity to give students handson experience with similarity and scale drawings in an engaging context.
In her blog, "eat play math," Lisa Winer discussed her experience presenting two classic problems, Einstein's Puzzle (a logic problem) and The Locker Problem (a number theory problem in disguise).
In her blog, "eat play math," Lisa Winer discussed her experience presenting two classic problems, Einstein's Puzzle (a logic problem) and The Locker Problem (a number theory problem in disguise).
In his blog "Singapore Maths Tuition," William Wu gives us a new take on an old idea with a blog post on the rational parametrization of a circle.
Zor Shekhtman introduced his ambitious Unizor project in 2008, in which he has created/collected hundreds of lectures and exams in advanced mathematics for high school students who want to dig into their curriculum in a deeper way. The site, unizor.com, emphasizes problem solving, proving theorems, and mathematical creativity.
Zor Shekhtman introduced his ambitious Unizor project in 2008, in which he has created/collected hundreds of lectures and exams in advanced mathematics for high school students who want to dig into their curriculum in a deeper way. The site, unizor.com, emphasizes problem solving, proving theorems, and mathematical creativity.
Thursday, September 18, 2014
Thursday, September 11, 2014
Thursday, September 4, 2014
Wednesday, August 27, 2014
Thursday, August 21, 2014
Thursday, August 14, 2014
Thursday, August 7, 2014
Thursday, July 31, 2014
Thursday, July 24, 2014
Thursday, July 17, 2014
Thursday, July 10, 2014
Thursday, July 3, 2014
Thursday, June 26, 2014
Thursday, June 19, 2014
Thursday, June 12, 2014
Thursday, June 5, 2014
Thursday, May 29, 2014
Tuesday, May 27, 2014
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PLAYFUL MATH BLOG CARNIVAL #163
BLOG CARNIVAL #163....LET'S GO! Fun fact: The number 163 is prime, which we can prove simply by showing that it is not divisible by 2, 3...

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