The late astronomer Carl Sagan said: "Science is much more a way of thinking than a body of knowledge."

A truly successful nurturing system will produce a person who thinks and acts with scientific rigour, rather than a walking encyclopaedia.

Science occupies an important place in our schools. Of the four subjects tested in the Primary School Leaving Examination, the two languages and mathematics are really life skills, while science is heavily content-oriented.

To be effective, the science learning process must be affective - involving hands-on, provocative and multi-sensory experiences. And since science is all about how the physical world works, teaching should include a dose of real life.

Some things can get in the way.

Even as we acknowledge that assessment is indispensable in school, it is possible to kill a child's interest - even in pop music - by making it examinable.

Let's consider the recent brouhaha over the need to be precise in answering exam questions. That's not unreasonable, but wisdom is needed both in asking the question, and grading the answer.

Take a typical classroom question: "Does this tiny cup of coffee contain more heat than the large glass of cold lemonade?"

The words "tiny", "large" and "cold" are all imprecise terms, but the real transgression here is in the use of the word "heat".

In thermodynamics, heat cannot be contained. It comes into being only when thermal energy flows from one point to another.

If the question is vague, the student cannot possibly provide an acceptable answer. So a teacher needs to have a strong grounding in the basic concepts of science to properly rate a student's answer.

We should be uncompromisingly clear when presenting basic scientific concepts, but take care not to be too pedantic over the use of everyday English.

So never confuse a squirrel with a bird, but don't quibble too much that a "flying squirrel" glides and doesn't actually fly.

Science and the scientific method are exact and powerful.

But in an ever-evolving field of knowledge, new truths supersede old ones.

In Sir Isaac Newton's era, for example, time was absolute, but Albert Einstein later proved that time can slow down if you travel fast enough.

Newton thought light consists of particles, but British scientist James Clerk Maxwell showed that light is part of a spectrum of electromagnetic waves.

Today, we accept that light behaves like both a stream of particles, as well as waves. Who knows what tomorrow will bring?

So why do we learn science?

In primary school, I would advocate that teachers instil a hint of scientific thought, and inspire a visceral sense of wonder and inquiry, rather than just dole out facts. To explain our place in the universe, for instance, show children the natural night sky filled with stars - don't just point to a page in a book or on the Internet.

Many city children have never even seen the Milky Way in its full glory, and, thus, never fully appreciate the vastness of space.

Similarly, to understand atmospheric pressure, the simple experiment of water being held in an inverted cup by a mere piece of paper is extremely effective.

How do we assess the success of such instruction methods?

I doubt there is an effective system to gauge a child's inspiration. And that matters a lot more than marks in a report card. When the difference between a full mark and zero can be determined by grammar and syntax, a science score is meaningless.

The primary school years are when a child's brain is being hard-wired, so we want to develop in them a love for the subject.

Having a passionate and fun teacher who is not preoccupied with grades will go a long way.

The science teacher will also be confronted with many situations in which he would do well to avoid the "single right answer".

There are so many questions, such as "What colour is a leaf?", or "Are there three states of matter or four?", or "Is a virus alive?", and so on, that have no single answer.

The teacher should be confident enough to say "I don't know" since this stimulates more curiosity.

One's secondary school and teenage years are the time to become equipped with essential scientific knowledge necessary for everyday life. We want our young people to know that the physical world can be understood, as well as cause and effect in nature.

The noisy cockerel does not make the sun rise. And while having an extra chromosome and Down syndrome are correlated, causality is not clear.

On the other hand, science has ascertained many things for us. We know that dengue is caused by a virus that is carried by a special mosquito. We also know the habits of the mosquito vector.

Also important to know are the practical things, such as the safe use of appliances, properties of chemicals and how the human body works. That drinking a concoction of joss-stick ash does not cure diseases, that a spray of suspended powdery flour in the air is potentially explosive and why eye muscles deteriorate with too much Internet gaming.

This is knowledge that will help us to navigate life.

Most importantly, the student imbibes logic and objectivity, and learns to look for answers using the scientific method.

As the years roll by, we adults should continuously embrace scientific thought and new knowledge. While not everyone will want to pursue more rigorous studies, it is important to stay in touch with science. It could be just by reading popular science pages, or watching documentaries.

Hopefully, the strong foundation laid down in schools will foster some enthusiasm. By reminding us why we learn science, schools (and parents) can "teach" in the most effective manner. And whatever testing system we devise must also lead us further down the road to producing the most scientifically literate and proficient people.

On a personal level, I find science and maths rather tough, like most people do. It can be demanding, dry and abstract. But once you cross a certain threshold, the beauty of science unveils itself.

Everything connects back into a coherent whole. For example, the rotation of the Earth results in day and night. And by some quirk, our planet is tilted some 23 degrees to the orbit round the Sun, which results in the four seasons.

The sunlight that gives us warmth also sustains life on Earth. This same sunlight will destroy us if we don't figure out a solution to global warming.

But then again, some time in the distant future, the Sun will explode and blow away our planet.

Isn't it all awesome to know?

Meanwhile, the festivals in the lunar calendar, the date for Easter each year, Hari Raya, and so many of our traditions derive from the movement of the heavenly bodies.

And that's just basic astronomy.

Contemplate the vast influence exerted by medicine, electronics, communications and transport, and we know what can best inspire excellence in our young.

So let's not obsess over grades.

Focus instead on developing a person who finds joy in discovering new truths in the world around us, and who feels drawn to a pursuit that is the bedrock of mankind's progress.