Posted in What is mathematics

What is good mathematics?


Terence Tao

It may not be for the majority of learners but it remains an important goal of math education in the basic level to hone future mathematicians who in turn are expected to produce good mathematics.  This post presents Terence Tao‘s personal thoughts on what good quality mathematics could mean. Terence was a child prodigy. When he was 24, he was promoted to full professor at UCLA and remains the youngest person ever appointed to that rank by the institution. Terence Tao currently holds the James and Carol Collins chair in mathematics at the University of California, Los Angeles. He was one of the recipients of the 2006 Fields Medal.

What I like about Terence’ descriptions of good quality mathematics is that it is possible at K-12 levels for students to actually produce good mathematics within the universe of their knowledge given the right motivation and challenge, the appropriate activity, enough opportunity, etc. I think students have the right to participate in the production of mathematical knowledge. Activities such as problem solving, mathematical investigations, and  modelling are all about training students to “produce” good mathematics.

Good mathematics could refer to any of the following:
  1. Good mathematical problem-solving (e.g. a major breakthrough on an important mathematical problem);
  2. Good mathematical technique (e.g. a masterful use of existing methods, or the development of new tools);
  3. Good mathematical theory (e.g. a conceptual framework or choice of notation which systematically unifies and generalises an existing body of results);
  4. Good mathematical insight (e.g. a major conceptual simplification, or the realisation of a unifying principle, heuristic, analogy, or theme);
  5. Good mathematical discovery (e.g. the revelation of an unexpected and intriguing new mathematical phenomenon, connection, or counterexample);
  6. Good mathematical application (e.g. to important problems in physics, engineering, computer science, statistics, etc., or from one field of mathematics to another);
  7. Good mathematical exposition (e.g. a detailed and informative survey on a timely mathematical topic, or a clear and well-motivated argument);
  8. Good mathematical pedagogy (e.g. a lecture or writing style which enables others to learn and do mathematics more effectively, or contributions to math- ematical education);
  9. Good mathematical vision (e.g. a long-range and fruitful program or set of conjectures);
  10. Good mathematical taste (e.g. a research goal which is inherently interesting and impacts important topics, themes, or questions);
  11. Good mathematical public relations (e.g. an effective showcasing of a mathematical achievement to non-mathematicians, or from one field of mathematics to another);
  12. Good meta-mathematics (e.g. advances in the foundations, philosophy, history, scholarship, or practice of mathematics);
  13. Rigorous mathematics (with all details correctly and carefully given in full);
  14. Beautiful mathematics (e.g. the amazing identities of Ramanujan; results which are easy (and pretty) to state but not to prove);
  15. Elegant mathematics (e.g. Paul Erdos’ concept of “proofs from the Book”; achieving a difficult result with a minimum of effort);
  16. Creative mathematics (e.g. a radically new and original technique, viewpoint, or species of result);
  17. Useful mathematics (e.g. a lemma or method which will be used repeatedly in future work on the subject);
  18. Strong mathematics (e.g. a sharp result that matches the known counterexamples, or a result which deduces an unexpectedly strong conclusion from a seemingly weak hypothesis);
  19. Deep mathematics (e.g. a result which is manifestly non-trivial, for instance by capturing a subtle phenomenon beyond the reach of more elementary tools); Intuitive mathematics (e.g. an argument which is natural and easily visualisable);
  20. Definitive mathematics (e.g. a classification of all objects of a certain type; the final word on a mathematical topic);

You can find the link to the complete paper in Terence Tao’s WordPress blog. You may also want to read Terence’s books.

Posted in Mathematics education

Theories and ideas behind the math lessons in this blog

I have put together in this post some of the ideas behind the kind of mathematics teaching I promote. As I stated in the subheadings of this blog, the articles and lessons I write here are not about making mathematics easy because it isn’t but about making mathematics makes sense because it does. Before reading any of the articles below, I suggest read the About page first and what I think mathematics is. I hope I make sense in the following articles. Click here for the list of math lessons.

To understand mathematics is to make connection

Mathematics is an art

Teaching through Problem Solving

Mathematical habits of mind

What is mathematical investigation?

Exercises, Problems, and Math Investigations

Why it is bad habit to introduce math concepts through their definitions

What is reasoning? How can we teach it?

What is the role of visualization in mathematics?

Making generalizations in mathematics

What is abstraction in mathematics?

I also have a new blog about research studies in mathematics teaching and learning.

Posted in Math Lessons

Math Lessons in Mathematics for Teaching

This is a collection of math lessons posted in this blog.  Most if not all of the lessons use the strategy teaching through problem solving or through mathematical investigation. I believe that school mathematics is about teaching students how to think mathematically first and learning the mathematics second so  math lessons should be designed so that students are engaged in thinking mathematically. This is something that should not be left to chance.

  1. How to grow algebra eyes and ears
  2. How to teach the inverse function
  3. How to teach the derivative function without really trying
  4. How to scaffold problem solving in geometry
  5. What is a coordinate system?
  6. How to teach triangle congruence through problem solving
  7. Teaching the meaning of equal sign
  8. Geometry lesson: Collapsible chair model
  9. Teaching negative numbers via the numberline with a twist
  10. Introducing negative numbers
  11. Teaching with GeoGebra – Investigating coordinates of points
  12. Teaching simplifying and adding radicals
  13. Teaching with GeoGebra: Squares and Square Roots
  14. Teaching trigonometry via problem solving
  15. Introducing positive and negative numbers
  16. Teaching subtraction of integers
  17. Algebraic thinking and subtracting integers – Part 2
  18. Subtracting integers using tables- Part 1
  19. Teaching the absolute value of an integer
  20. Teaching with GeoGebra: Constructing polygons with equal area
Posted in Number Sense

Teaching algebraic thinking without the x’s

Students need not wait till they meet Mr. x to learn about algebra. In fact, the best way to learn about algebra is to learn it while there aren’t x’s yet; when all the learners need to deal with are concepts that still make sense to them. Here is a list of tips and ways for teaching algebraic thinking as pupils learn about numbers and number operations.

1. Vary the “orientations” of the way you write number sentences.

For example, 5 + 20 = 25 can be written as 25 = 5 + 20. The first expression is about ‘doing math’, the second engages students about ‘thinking about the math’, the different representations of the number 25. The thinking involved in the second one is ‘algebraic’.

2. Be mindful of the meaning of equal sign

If you want to ask your learners to find, for example, the sum of 15 plus 6, do not write 15 + 6 =___. It’s a recipe for misconception of the meaning of equal sign. I recommend: What numbers is the same as (or equal to) 15 + 6? Better, What number phrases are the same as (or equal to) 15 + 6? This last one promotes algebraic thinking.

3. Encourage learners to generalize. Continue reading “Teaching algebraic thinking without the x’s”