Posted in Math blogs

Math Teachers at Play blog carnival #50

When I sign-up to host the May edition of Math Teachers At Play blog carnival organized by Denise of Let’s Play Math blog, I didn’t know it will be its 50th edition. Wasn’t I lucky? It’s a milestone for MTAP. Kudos to the organizer and supporters of MTAP. But I got one little problem. It is a tradition in math blog carnivals to always starts with saying something mathematically significant about the n in its nth edition! Oh dear. Things I associate with the number 50 are mostly non-mathematical  like golden anniversaries!

the number 50

Wikipedia to the rescue:

Fifty is the smallest number that is the sum of two non-zero square numbers in two distinct ways: 50 = 12 + 72 and 50 = 52 + 52. It is also the sum of three squares, 50 = 32 + 42 + 52.

And I didn’t know that until I hosted this carnival! I’m a teacher I have to ask: “So what’s the next bigger number to 50 that is the sum of two non-zero square numbers in two distinct ways?”; “What are other numbers that can be expressed as a sum of the squares of consecutive numbers?”; “What about those numbers that can be expressed as sum of cubes?”;…  There is always something to investigate in math. One of the major objectives of school math is to get students into this thinking habit without us telling them to do so but I’m digressing from my topic now. Let’s get to the great posts submitted for this edition.

1 – How many bricks are in this building? Says its author Paul Murray: This is an activity I’ve used for years and recently wrote up for a class.  It integrates many problem-solving methods, multiplication, addition, and place value concepts, estimation, and organization of data.   It also takes the students outside with a clearly defined task to accomplish.

2 – Wolfram Alpha. Says it author Coleen Young: This page is from the student version of my blog and has several slideshows showing the syntax for WolframAlpha including a fun show at the end on the sillier questions one can ask! I started this student version because they can just be given the link. One of my former students emailed me recently to tell me how much she was using WolframAlpha at university.

3 – New intuitive ways of learning math by Mohamed Usama. Says Mohamed,  “I am a student and I love game programming. CREVO is just my virtual startup where I publish all my ideas and other news. Math Operations is a game that won local game development competition. That time, I developed this game in Flash. It was just a 48 hour competition but still idea was executed well. At the time when I was receiving my prize I announced that soon, I’ll publish it for all Android devices and here it is. I finally developed this game for all Android & Amazon Kindle Fire devices. Designed graphics (SD & HD) for tablet as well. Last week I published my new version 1.5 and its available on Google Play (Amazon is still reviewing it). I hope you people will love it. I need high support because I really want to make games for kids, education sector is what my target is.

4 – Guess my rule says its author John Golden is a story of an algebra lesson based on a simple, common social game.

5 – You Want School Reform?  Brace Yourself…. submitted by Matt Wilson. Writes Matt in the post “Anybody building a house needs to start by building a foundation, but our system is teaching foundation building without ever teaching anyone what a house actually is…”

6 – Missing Angles says the author of Five Triangles is a non-trivial math problem for middle school students requires some actual thinking.

7 – An elegant solution: An algebra problem from 1798 by Dan Pearcy. Says Dan, I stumbled across this great little problem on John Cook’s blog (The Endeavour) during the weekend. The reasons that it’s so great are two-fold: (1) Most people think they’ve solved it when they have four solutions from their equation when in fact they have not considered that the equation could be written in four different ways. (2) The solutions are so elegant. Possibly because they are all based around the golden ratio.

8 – More on Microsoft Equation Editor says John Chase is a follow-up and more in-depth discussion of http://mrchasemath.wordpress.com/2012/03/15/microsoft-office-equation-editor/.

9 –  Sidewalk Math: Functions. No name was supplied but its from a blog called “The Map is Not the Territory”.

10 –  9 TED talks to get your teens excited about math shared by Caroline Mukisa. A great collection.

11 – Thinking (and teaching) like a mathematician. Says Denise, “Being ‘good at math’ means much more than being able to work with numbers. It means making connections, thinking creatively, seeing familiar things in new ways, asking “Why?” and “What if?” and “Are you sure?” If we want to teach real mathematics, we teachers need to learn to think like mathematicians. We need to see math as a mental game, playing with ideas.”

12 – Tiger’s Mum presents Geometry: 2D and 3D posted at The Tiger Chronicle.

13 –  Another Proof of the Sum of the First n Positive Integers and  The Mathematics of the Poles shared by Guillermo Bautista. The first shows a geometric proof and the second post is a discussion on the connection among poles of the earth, the latitudes and longitudes, and the polar coordinates.

14 – Planning and Analyzing Mathematics Lessons in Lesson Study by Erlina Ronda (that’s me). This is a powerpoint presentation for researching lessons with your colleagues.  Lesson study is schools-based teacher-led professional development model.

15 – The nature of math vs the nature of school math. This is my top post this month. Everybody is concerned about the great divide between math and math education.

The next MTap Carnival will be hosted in  Math Mama Writes.

 

Posted in Curriculum Reform

The nature of math vs the nature of school math

The mathematics experienced by students is so much different from the real nature
of math. What a tragedy!

What is the nature of mathematics?
  1. Mathematics is human. It is part of and fits into human culture. It is NOT an abstract, timeless, tensely, objective reality…
  2. Mathematical knowledge is fallible. As in science, mathematics can advance by making mistakes and then correcting them…
  3. There are different versions of proof or rigor. Standards of rigor can vary depending on time, place, and other things. Think of the computer-assisted proof of four color theorem in 1977…
  4. Empirical evidence, numerical experimentation and probabilistic proof all can help us decide what to believe in mathematics…
  5. Mathematical objects are a special variety of a social-cultural-historical object …They are shared ideas like Moby Dick in literature and the Immaculate Conception in religion.

The above description of the nature of mathematics is by Reuben Hersh,  from his article “Fresh Breezes in the Philosophy of Mathematics published in American Mathematical Monthly Aug-Sept, 1995 issue. He is also the author of the now classic What Is Mathematics, Really?.

What is the ‘nature’ of school mathematics?

The following is a 2002 critic of the US k-12 mathematics by Paul Lockhart in A Mathematician’s Lament.  It’s also true in my part of the globe.

The Standard of K-12 mathematics according to Lockhart:

LOWER SCHOOL MATH. The indoctrination begins. Students learn that mathematics is not something you do, but something that is done to you. Emphasis is placed on sitting still, filling out worksheets, and following directions. Children are expected to master a complex set of algorithms for manipulating Hindi symbols, unrelated to any real desire or curiosity on their part, and regarded only a few centuries ago as too difficult for the average adult. Multiplication tables are stressed, as are parents, teachers, and the kids themselves.

MIDDLE SCHOOL MATH. Students are taught to view mathematics as a set of procedures, akin to religious rites, which are eternal and set in stone. The holy tablets, or “Math Books,” are handed out, and the students learn to address the church elders as “they” (as in “What do they want here? Do they want me to divide?”) Contrived and artificial “word problems” will be introduced in order to make the mindless drudgery of arithmetic seem enjoyable by comparison.

ALGEBRA I. So as not to waste valuable time thinking about numbers and their patterns, this course instead focuses on symbols and rules for their manipulation…. The insistence that all numbers and expressions be put into various standard forms will provide additional confusion as to the meaning of identity and equality. Students must also memorize the quadratic formula for some reason.

GEOMETRY. Isolated from the rest of the curriculum, this course will raise the hopes of students who wish to engage in meaningful mathematical activity, and then dash them. Clumsy and distracting notation will be introduced, and no pains will be spared to make the simple seem complicated. This goal of this course is to eradicate any last remaining vestiges of natural mathematical intuition, in preparation for Algebra II.

ALGEBRA II. The subject of this course is the unmotivated and inappropriate use of coordinate geometry. Conic sections are introduced in a coordinate framework so as to avoid the aesthetic simplicity of cones and their sections. Students will learn to rewrite quadratic forms in a variety of standard formats for no reason whatsoever. Exponential and logarithmic functions are also introduced in Algebra II, despite not being algebraic objects, simply because they have to be stuck in somewhere, apparently.

TRIGONOMETRY. Two weeks of content are stretched to semester length by masturbatory definitional runarounds. Truly interesting and beautiful phenomena, such as the way the sides of a triangle depend on its angles, will be given the same emphasis as irrelevant abbreviations and obsolete notational conventions, in order to prevent students from forming any clear idea as to what the subject is about. Students will learn such mnemonic devices as “SohCahToa”…