15% of questions in PSLE classified as challenging each year

 I personally think this 15% distribution is fair. 

- The majority of questions are accessible to most students, with a small number of questions allowing stronger students to demonstrate their mastery of the subject.

- Each pupil's marks in the new scoring system reflects the child's mastery of the subject as there is no bell curve or quotas imposed on the number of pupils for each Achievement Level (AL) band.

There is one nice Chinese article talking about PSLE Mathematics. Actually two thirds of the students are able to cope with the challenging questions. 

They quoted one simple modeling question below, arguing that the primary students now are taught to solve such question by modeling instead of traditional algebra way.

Does Maths have to be so difficult? (schoolbag.edu.sg)

Of course, I asked my 10 years old boy to solve this question in both ways. He was taught solving the question in algebra way by me in the past. I always believe there are many ways to solve a mathematic question. In fact, if you see the way he solved the question using modeling method, some of the steps are actually algebra way, just that you did not interpret them in a formula/equation. He is able to solve the question with both methods correctly. That's good.

I will be worried too if a primary student master in modeling method but failed to understand the true algebra meaning. It is because once they proceed to the secondary school level, they have to throw away all the modeling method but master in algebra method instead. Nevertheless, I believe those who master in modeling, they will eventually realize that all these modeling can be re-interpreted in algebra method too. They are somewhat identical.

The next challenging part in algebra (during the secondary school) will be setting up/develop the equations correctly. For example: 2 unknowns 2 equations, 3 unknown 3 equations, etc. .

Happy learning!