As children face their final month of revision before the exam season starts, many parents are looking for the words to motivate their offspring. But could they be mistakenly praising the value of ability over effort, asks Matthew Syed.

Take a glance at these expressions of encouragement:

"You learned that so quickly, you're so smart!"

"Look at that drawing. Are you the next Picasso or what?"

"You're so brilliant - you passed that exam without really studying!"

They come across as precisely the kind of confidence-boosting statements that should be given to children or, indeed, anyone else. Such phrases are used in homes and classrooms every day, particularly with exams looming.

But are they benign? Or could they unlock the reason why so many children are failing at school and elsewhere?

Intelligence-based praise orients the receiver towards the fixed mindset - it suggests to them that intelligence is of primary importance rather than the effort through which intelligence can be transformed

To find out we need to take a quick detour into the science of expertise, and ask a question. Where does excellence come from? For a long time, it was thought the answer to this hinged, to a large degree, on genetic inheritance. Or, to put it another way, it is all about talent.

It turns out that this is mistaken. Dozens of studies have found that top performers - whether in maths, music or whatever - learn no faster than those who reach lower levels of attainment - hour after hour, they improve at almost identical rates.

The difference is simply that high achievers practise for more hours. Further research has shown that when students seem to possess a particular gift, it is often because they have been given extra tuition at home by their parents.

This is not to deny that some kids start out better than others - it is merely to suggest that the starting point we have in life is not particularly relevant.

Why? Because, over time, with the right kind of practice, we change so dramatically. It is not just the body that changes, but the anatomy of the brain.

A study of pianists, for example, showed that the area of the brain governing finger movement is substantially larger than for the rest of us - but it did not start out like this; it grew with practice.

The question of talent versus effort would not matter terribly much if it was merely theoretical. But it is so much more than that. It influences the way we think, feel, and the way we engage with our world.

Mindset experiments Computer studies students received lessons on importance of growth mindset. It resulted in a dramatic improvement in test scores after a six-week intervention

Students at Stanford University were encouraged towards the growth mindset in a workshop. At the end of term, these students had earned significantly higher grade point averages than the control group

To see how, consider a youngster who believes excellence is all about talent - labelled the "fixed mindset". Why would she bother to work hard?

If she has the right genes, won't she just cruise to the top? And if she lacks talent, well, why bother at all? And who can blame a youngster for this kind of attitude, given the underlying premise?

If, on the other hand, she really believes that effort trumps talent - labelled the "growth mindset" - she will persevere. She will not see failure as an indictment, but as an opportunity to adapt and grow. And, if she is right, she will eventually excel.

What a young person decides about the nature of talent, then, could scarcely be more important.

Think how often you hear children saying "I just lack the brain for numbers" or "I don't have the coordination for sports". These are direct manifestations of the fixed mindset, and they destroy motivation.

Those with a growth mindset, on the other hand, do not regard their abilities as set in genetic stone. These are the youngsters who approach tasks with gusto. "I may not be good at maths now, but if I work hard, I will be really good in the future!"

Image caption Many schools already praise effort as much as achievement

So, how do we orient our children to the growth mindset? A few years ago, Carol Dweck, a leading psychologist, took 400 students and gave them a simple puzzle.

Afterwards, each of the students were given six words of praise. Half were praised for intelligence: "Wow, you must be really smart!" The other half were praised for effort: "Wow, you must be hard working!"

Dweck was seeking to test whether these simple words, with their subtly different emphases, could make a difference to the student's mindsets. The results were remarkable.

After the first test, the students were given a choice of whether to take a hard or an easy test.

A full two-thirds of the students praised for intelligence chose the easy task - they did not want to risk losing their "smart" label. But 90% of the effort-praised group chose the tough test - they wanted to prove just how hard working they were.

Then, the experiment came full circle, giving the students a chance to take a test of equal difficulty to the first test.

The group praised for intelligence showed a 20% decline in performance compared with the first test, even though it was no harder. But the effort-praised group increased their score by 30%. Failure had actually spurred them on.

Image caption Many people believe that talent is a fixed quality

And all these differences turned on the difference in six simple words spoken after the very first test.

"These were some of the clearest findings I've seen," Dweck said. "Praising children's intelligence harms motivation and it harms performance."

Intelligence-based praise orients the receiver towards the fixed mindset - it suggests to them that intelligence is of primary importance rather than the effort through which intelligence can be transformed.

And this takes us right back to those expressions of praise we started out with. They all sounded like confidence-boosting statements. But now listen to the subliminal messages in the background:

"If I don't learn something quickly, I'm not smart."

"I shouldn't try drawing anything hard or they'll see I'm no Picasso."

"I'd better quit studying or they won't think I'm brilliant."

This reveals a radical new approach to the way we engage with children - that we should praise effort, never talent; that we should teach kids to see challenges as learning opportunities rather than threats; and that we should emphasise how abilities can be transformed.

Experiments from around the world have shown that when parents and teachers adopt this approach, and stick to it, the results are remarkable.

Matthew Syed is the author of Bounce: The Myth of Talent and the Power of Practice.