I have the misfortune to be great friends with a woman who has the most self-disciplined children I know. She has never had to tell her sons that it is time to do homework, practise the piano or pick up their guitars. They use their spare time doing creative and meaningful things: drawing comic strips, writing extremely long stories, composing and performing songs. Worse, they are not even snotty, but pleasant and engaging kids. The parents don’t push them. They just really want to do these things.

Another friend has a very self-disciplined daughter who does brilliantly at school and in her spare time goes swimming and riding, learns the piano, as well as dancing, drama and gymnastics. Her mother makes vague noises about overscheduling, but the girl is energised and excited by her rich, busy life.

Back at my house, the kids seem to be skulking around the periphery of a toxic childhood, lacking the self-discipline to do anything that requires practice. Underscheduled, and underwhelmed by the many after-school activities on offer, they always have an explanation why some sport or music or dance class is rubbish. I have let them drop out of these things because it seemed counter-productive and counter-intuitive to have to cajole or bully them into doing something they were meant to be enjoying.

Now, at 10 and 13, my son and daughter find that their peers who stuck to things are getting more accomplished and confident at the sports, music and dancing they have been practising for years. So I’ve become more hard line, asking my kids to try new activities at least five times before deciding they don’t like it. But is it too late for me to change my “whatever” kids into “sure, why not” kids? Are motivated and self-disciplined children born that way or are they nurtured by parents who are doing the right thing?

It’s not a matter of nature or nurture, says Sam Goldstein, a psychologist and co-author, with Robert Brooks, of Raising a Self-Disciplined Child, a book that helps parents to understand and work with the mindset of an unmotivated child. The book looks beyond the problem of children reluctant to sign up for after-school clubs to include those seen by Goldstein in a clinical setting whose lack of self-control leads to appalling, unruly behaviour.

Goldstein and Brooks are in no doubt as to the importance of their subject matter. “A large body of research has demonstrated that children who can resist temptation (a simple application of self-discipline at all ages) fare significantly better than their more impulsive peers when they enter their adolescent years. . . The power of self-discipline to affect the course of a child’s and adult’s life should never be underestimated,” they write.

Goldstein holds that both nature and nurture have a role to play when it comes to self-discipline. “Ideally, we need a word that describes both,” he says. “We say ‘biopsychosocial’, which takes in biological and social factors.” Goldstein and Brooks argue that even if your child is not predisposed towards being self-disciplined, it is possible to encourage him or her through empathy – or seeing things from the child’s point of view.

A great way to do this, they say, is to ask yourself how you would feel if someone spoke to you the way that you speak to your child. So, in my case, instead of berating my daughter for always giving up on things, I should be asking (hint: never say always): “Why did you give up on the things you’ve tried? How can I help you find something you’d like to stick at?”

Another big parental influence on self-discipline is how the parent administers their own discipline. A positive approach based on rewarding the good rather than punishing the bad fosters good self-discipline. It also involves modelling the sort of behaviour you wish your child to display. So, to scream, “I wish you two would stop bloody shouting at each other” is less effective than not shouting at all. To those who already do this, it will seem obvious, but to seasoned screamers like me, not shouting has turned out to be a powerful tool in making my seemingly dysfunctional family live more harmoniously.

This, in turn, has had a knock-on effect on self-discipline. So instead of exploding, “I can’t believe you left your homework until the last minute, again!” I say, “I think you might need some help organising your time. How can you fix that? Can I help?” Yes, it sounds scripted and strained, but it’s a better script than the old one. I’m shouting less and things are getting done.

Brooks and Goldstein are also very big on what they call “islands of competence”. This entails helping your child to find the thing he or she is good at and encouraging it. Here I become unstuck because to find this island, the child has to stick to something long enough to figure out if he or she is any good at it.

Goldstein relates a story of a boy who said he was not good at anything until his mother piped up that he was really good at making her angry. It’s a good one-liner, but it doesn’t solve the chicken or egg problem in my family, which is that competence requires actually doing something. Goldstein insists: “You have to help them to keep looking. Everybody has something. But the child has to have input in choosing the activity.” In the past few weeks my son has discovered a love for indoor rock climbing, and my daughter has agreed to try the after-school drawing club. It’s early days, but it’s fair to say the mindset has shifted.

Our conversations have changed from inflammatory to something approaching rational problem-solving. Shouted reminders have morphed into gentle hints and for the first week in living memory both my children have sat down to do homework without being prompted.

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