Posted in Mathematics education, Teaching mathematics

Three Levels of Math Teachers Expertise

Level 1 – Teaching by telling

The teachers at Level 1 can only tell students the important basic ideas of mathematics such as facts, concepts, and procedures. These teachers are more likely to teach by telling. For example in teaching students about the set of integers they start by defining what integers are and then give students examples of these numbers. They give them the rules for performing operations on these numbers and then provide students exercises for mastery of skills. I’m not sure if they wonder later why students forget what they learn after a couple of days.

Levels of teaching

Level 2 – Teaching by explaining

Math teachers at Level 2 can explain the meanings and reasons of the important ideas of mathematics in order for students to understand them. For example, in explaining the existence of negative numbers, teachers at this level can think of the different situations where these numbers are useful. They can use models like the number line to show how negative numbers and the whole numbers are related. They can show also how the operations are performed either using the number patterns or through the jar model using the + and – counters or some other method. However these teachers are still more likely to do the demonstrating and the one to do the explaining why a particular procedure is such and why it works. The students are still passive recipients of the teachers expert knowledge.

Level 3 – Teaching based on students’ independent work

At the third and highest level are teachers who can provide students opportunities to understand the basic ideas, and support their learning so that the students become independent learners. Teachers at this level have high respect and expectation of their students ability. These teachers can design tasks that would engage students in making sense of mathematics and reasoning with mathematics. They know how to support problem solving activity without necessarily doing the solving of the problems for their students.

The big difference between the teacher at Level 2 and teachers at Level 3 is the the extent of use of students’ ideas and thinking in the development of the lesson. Teachers at level 3 can draw out students ideas and use it in the lesson. If you want to know more about teacher knowledge read Categories of teacher’s knowledge. You can also check out the math lessons in this blog for sample. They are not perfect but they are good enough sample. Warning: a good lesson plan is important but equally important is the way the teacher will facilitate the lesson.

Mathematical Proficiency

The goal of mathematics instruction is to help students become proficient in mathematics. The National Research Council defines ‘mathematical proficiency’ to be made up of the following intertwined strands:

  1. Conceptual understanding – comprehension of mathematical concepts, operations, and relations
  2. Procedure fluency – skill in carrying out procedure flexibly, accurately, efficiently, and appropriately
  3. Strategic competence – ability to formulate, represent, and solve mathematical problems
  4. Adaptive reasoning – capacity for logical thought , reflection, explanation, and justification
  5. Productive disposition – habitual inclination to see mathematics as sensible, useful, and worthwhile, coupled with a belief in diligence and one’s own efficacy. (NRC, 2001, p.5)

I think it will be very hard to achieve these proficiencies if teachers will not be supported to attain Level 3 teaching I described above. No one graduates from a teacher-training institution with a Level 3 expertise. One of the professional development teachers can engage to upgrade and update themselves is lesson study. The  book by Catherine Lewis will be a good guide: Lesson Study: Step by step guide to improving instruction.

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 Mathematics education

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

In my earlier post on the meaning of understanding, I describe understanding of mathematics as making connections: To understand is to make connections. These connections are not done in random.  Concepts are linked with other concepts in order to create a richer image for the new concept that is being learned. To understand therefore is to form concept image. And a concept image is not formed by defining the concept. The definition of a concept is different from the concept image. Let me share with you a an excerpt from my paper which discusses this idea. You can view the references here.

Understanding the definition does not imply understanding the concept. In order to understand a concept one must have a concept image for it. One’s concept image includes all the non-verbal entities, visual representations, impressions and experiences that are created in our mind by a mention of a concept name (Vinner, 1992). Vinner stressed that the concept definition is not the first thing that is learned in understanding a concept but the experiences associated with it, which becomes part of one’s concept image. Vinner believes that in carrying out cognitive tasks, the mind consults the concept image rather than the concept definition. Continue reading “Why it is bad habit to introduce math concepts through their definitions”

Posted in Elementary School Math, Number Sense

Teaching negative numbers via the numberline with a twist

One popular way of introducing the negative numbers is through the number line. Most textbooks start with the whole number on the number line and then show to the students that the number is decreasing by 1. From there, the negative numbers are introduced. This seems to be something easy for students to understand but I found out that even if students already know about the existence of negative numbers having used them to represent situations like 3 degrees below zero as -3, they would not think of -1 as the next number at the left of zero when it is presented in the number line. They would suggest another negative number and some will even suggest the number 1, then 2, then so on, thinking that maybe the numbers are mirror images.

Here is an alternative activity that I found effective in introducing the number line and the existence of negative numbers.  The purpose of the activity is to introduce the number line, provide students another context where negative numbers can be produced (the first is in the activity on Sorting Situations and the second is in the task Sorting Number Expressions), and get them to reason and make connections. The task looks simple but for students who have not been taught integers or the number line the task was a problem solving activity.

Question: Arrange from lowest to highest value

When I asked the class to show their answers on the board, two arrangements were presented. Half of the class presented the first solution and the other half of the students, the second solution. Continue reading “Teaching negative numbers via the numberline with a twist”