Q: My daughter starts her schoolwork very slowly in the evening, and then later she feels she can’t complete it in time. She repeats this every day. What could be the reason? Thank you.A: There’s no doubt that your daughter prefers her recreational activities to doing homework. By procrastinating, she easily builds in an excuse for not having to finish her work. She’d rather not.There’s a simple behavioural principle known as the Premack Principle. It’s a principle of operant conditioning originally identified by David Premack in 1965. It says,:“Behaviour that happens reliably can be used as a reinforcer for behaviour that happens less reliably.” It might be better named Grandmom’s rule. In your daughter’s case, consider what she does reliably before she does her homework, e.g., e-mail, television watching, etc., and simply explain to her that completing her homework (unreliable) must come before it. You can help her set up a daily schedule, and she’ll complete her homework if she can’t get to other more exciting activities until her homework is finished.I don’t know how old your daughter is. For a young child, it’s easy to get these good habits started. For a teenager, it can be more of a struggle, but if she doesn’t learn self-discipline now, she’ll indeed be in trouble when she attends college.Q: Should you keep young kids in activities if they say they do not want to participate anymore (e.g., extracurricular activities such as sports and arts)? How do you change a child’s reaction to challenge? We have a four-year-old boy who shies away from challenge and seems like he is afraid to be wrong. Our older daughter is not that way. Thank you!A: Your outgoing, spirited older daughter may account for your son’s hesitations about challenge. No doubt, she gets praise for her accomplishments and does things well, while your son sees her success as beyond his ability. A 4-year-old does not need to have a great many extracurricular activities, but you can certainly insist that he completes them for at least a brief season. Most sports activities for preschoolers are not highly competitive, and if parents do not get too excited about winning or losing, kids usually do not become too sad either. They are only at the beginning ages of learning to cope with competition.One big reason that young children back away from challenge is if there has been too much “est” praise. I am referring to superlatives like smartest, best athlete, prettiest, etc. The praise could be given to either your son or daughter, and both would hear it as what you expect of them. Changing those praise statements to compliments without the “est” are much less pressuring. Parent praise conveys your expectations to children. If you refer to smart thinking, persevering, hardworking, kind, sensitive, good athlete, looking nice, children can live up to these. Living up to being smartest and best can feel competitive to young children who typically give up easily.Another possibility that could be encouraging your son’s fear of challenge is “referential” talk. That is, if he hears you or other people talking about his fear of failure or his timidity about activities, he will assume that he cannot change his behaviour. Referential talk about opposite behaviours, about his handling new activities well, working hard at challenges and persevering, will encourage him to believe in himself and build confidence. Be sensitive to what your son is hearing from grandparents, aunts, uncles and cousins as well. The words that surround him feel believable to him. There are also biological and temperamental differences among siblings. Your son may be inherently more shy or fearful than his sister.