It can’t all be Singapore Math…

This tweet posted by the National Council on Teacher Quality (@NCTQ) caught my eye:


Now, I’ve heard decomposing called “branching” but can’t remember ever seeing this in a Singapore textbook. Where did this problem come from?

It’s nice that NCTQ recognizes Singapore’s Math as “tops in the world.” But it’s discouraging to see methods and terminology that are not a part of the Singapore curriculum attributed to it. Especially in the context of the nasty debate about CCSS. And especially since Singapore’s math curriculum–with its rigor, coherence, and focus–is often cited as a basis for more rigorous standards, including CCSS.

The problem posted is based on the concept of “Number Bonds,” which calls for students to decompose numbers (this is the term used in Singapore and in all major Singapore Math® textbooks distributed in the U.S.). Below, I’ve posted some examples of how this concept is presented in Singapore Math® series available in both the U.S. and Singapore.

This matter points to my BIG concern: As publishers and others adapt Singapore’s Math for the American market, new approaches creep in. These often are not based on the curriculum that helped Singapore’s students go from mediocre to best in the world in a dozen years. I’ve written about this in my comparison of Singapore math textbook series available in the United States.

So my plea to NCTQ: please use examples from an actual Singapore mathematics text when citing the components that make it so successful. And feel free to ask if I can help you find those examples.

Number Bonds problems in Singapore Math® textbooks

Here are some materials covering Number Bonds and “decomposing” numbers from actual Singapore textbooks:

From My Pals are Here, the most-used materials in Singapore:

MPAH 3A Mental Addition

From the U.S. Edition of Primary Mathematics, available in North America since 2003:

PM US 3A Mental Addition

From the Common Core Edition of Primary Mathematics, released in the U.S. market in 2014:

PM CC 3A Mental Addition_0001

And finally, from Math in Focus:




Ugh! One more similar tweet from NCTQ.






You Can Bar Model Anything!

nauty nice bar model

A fourth grader at a school I worked with this year included this on a Christmas card for her teacher.

Happy Holidays and Best Wishes for an Outstanding New Year!



It Figures: Why U.S. Schools are Using Math from Singapore

Singapore’s Channel NewsAsia produces a show called “It Figures” described this way:

How do all the numbers and statistics on Singapore add up? IT FIGURES, figures it all out.

The premier episode of “It Figures Season 2” seeks “to find out why schools in the US are using our Math textbooks and adopting our way of teaching Math.”

Viewers were challenged to solve the Primary 5 Math problem below. Can you do it?

It Figures word problem

Most Singaporeans used Algebra.

Teacher Owen Lau uses the bar model method beginning at about 1:45:

[youtube][/youtube]From the Singapore TV Show It Figures.

Mr. Lau explains that “students can see better if a problem is presented in pictorial form.”  The following concepts are reinforced:

  • The Model Method: Drawing diagrams and bars to represent math problems visually.
  • The Model Method is not as abstract as Algebra, and helps students understand concepts instead of blindly apply math formulas.

The debut episode of “It Figures Season 2,” explaining the use of the Singapore curriculum in the US airs, on July 2, 2013.


Images and clip from the Channel NewsAsia website.


Bar Model Method challenges

Photo taken in a third grade classroom using Primary Mathematics. The teacher had posted the question on the board and students recorded the question and their solution in a math journal.



Understanding trumps tricks

My friend Allison (MIT graduate in Mathematics) recently explained why she struggled with inequalities as a child.

To help students remember which way the inequality sign pointed, the teacher drew an alligator mouth. You know the lesson. Here’s an example from

And the song lyrics:

And one from

And this simple shortcut or trick was the cause of all of Allison’s troubles with inequalities.

She explained: “everyone knows, the bigger fish eats the small fish”: