Posted in Curriculum Reform, Mathematics education

Knowledge of Teaching with ICT

In the 80’s, Lee Shulman introduced the concept of pedagogical content knowledge to differentiate it from content knowledge (CK) and knowledge of general pedagogy (PK). Pedagogical content knowledge or popularly known as PCK  is teachers’ knowledge of how a particular subject-matter is best taught and learned. Since Shulman introduced this concept, many others have contributed towards defining and describing it, the most important elements of its description include (1) knowledge of interpreting the content, (2) knowledge of the different ways of representing the content to the learner,  and (3) knowledge of learners’ potential difficulties, misconceptions, and prior conceptions about the content and related concepts. Click here for an example of a pedagogical concept map for teaching integers.

With the increasing dependence of almost everything to ICT, it is no longer a question of whether schools should integrate these technology in its curriculum. In fact it’s been decades since courses on ICT have been offered as a subject in many schools. But how about the use of technology in teaching traditional subjects like mathematics? Does knowledge of technology equip teachers to use it to teach effectively?

Some mathematics teachers jumped to it right away, used technology in teaching. Some teachers are still in testing-the-water mode. Some, until now, are still totally in the dark, sticking to their old method despite the availability of technology, oblivious to the reality that in today’s ICT-driven world, it’s the students who are the natives and the teachers are the migrants (heard this at an APEC Conference in Tokyo). The way students learn are influenced by their experiences with many forms of technology and the way these tools think and do things.

When the pen and the printing press were invented, everybody thought that they will give an end  to illiteracy (I heard this from the same conference). It didn’t take long for us to realize that it didn’t and can’t. The same can be said with computers, internet, softwares for teaching. Experience with these tools tell us that it is not enough to know how to use ICT  just us it was not enough to know mathematics content to teach mathematics so that students learn it with meaning and understanding .   Teachers must now be equipped not only with PCK but with TPCK – Technological Pedagogical Content Knowledge.

Punya Mishra and Matthew Koehler introduced this theoretical framework known as Technological Pedagogical Content Knowledge (TPACK) in 2005. The basic premise of TPACK is that a teacher’s knowledge regarding technology is multifaceted and that the optimal mix for the classroom is a balanced combination of technology, pedagogy, and content.

technological pedagogical content knowledgeThe figure at the right is popularly known as TPACK Framework (click image for source). It shows the kinds of knowledge teachers should posses. It can be used as framework for designing learning experiences for teachers and for planning, analyzing and describing the integration of technology in teaching.

 

Posted in Math blogs

Keeping Math Simple is now Mathematics for Teaching

Because this blog is dedicated to discussing mathematical ideas in the context of teaching them to k-12 audience I should rename it to “Mathematics for Teaching”. I do have some posts on other issues in mathematics education which frames some of the lessons discussed in the blog. Note that the domain name is now https://math4teaching.com. The old domain is http://keepingmathsimple.wordpress.com and still works, for now. Please update your links to this blog or better subscribe to my RSS or via email. Thank you.

Posted in Algebra

sorting pi, e, and root 2

Mathematicians, always economical,   love to categorize numbers according to their properties. This is because numbers belonging to the same category behave in the same way. You don’t have to deal with each one! That’s an economical way of preserving the energy demand of brain cells.  In the grades we give pupils tasks that involve sorting numbers. Whole numbers  can be sorted out as odd or even, prime or composite, for example. This is a very good way of giving the students a sense of how strict definitions are in mathematics and in understanding the nature of numbers. In the higher grades they meet other numbers which they can categorize as imaginary or real, transcendental or algebraic. The same mathematical thinking is used.

\pi is one of the most widely known irrational number. Ask a student or a teacher to give an example of an irrational number, the chances are they will give \pi as the first example or the second one, after square root of 2.  And of course at a distance third is the number e. Now, although they belong to the same set of numbers, the irrationals, they don’t really belong to the same category. For example, \pi and e are both irrationals but pi is transcendental and square root of 2 is algebraic.  The number e is also transcendental. Here’s a short and simple explanation.

 

 

A  transcendental number is one that cannot be expressed as a solution of ax^n+bx^(n-1)+…+cx^0=0 where all coefficients are integers and n is finite. For example, x=sqrt(2), which is irrational, can be expressed as x^2-2=0. This shows that the square root of 2 is nontranscendental, or algebraic.

It is very easy to prove that a number is not transcendental, but it is extremely difficult to prove that it is transcendental. This feat was finally accomplished for ? by Ferdinand von Lindemann in 1882. He based his proof on the works of two other mathematicians: Charles Hermite and Euler.

In 1873, Hermite proved that the constant e was transcendental. Combining this with Euler’s famous equation e^(i*?)+1=0, Lindemann proved that since e^x+1=0, x is required to be transcendental. Since it was accepted that i was algebraic, ? had to be transcendental in order to make i*? transcendental. Click here for source.

Of course understanding the proof of pi as a transcendental number is beyond the level of basic mathematics and hey, we don’t even talk about transcendental numbers before Grade 10. But students at this level can understand the expression ax^n+bx^(n-1)+…+cx^0=0 where all coefficients are integers and n is finite. With proper scaffolding or if they have been exposed to similar task of sorting numbers before  students can make sense of the logic and reasoning shown above which characterizes most of the thinking in mathematics.

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Image from http://studenthacks.org/wp-content/uploads/2007/10/pumpkin-pi.jpg