A child psychologist says giving children stickers, certificates and rewards for good behaviour could actually reduce their motivation to do the right thing.

Perth social psychologist Helen Street believes parents and schools are giving rewards in the mistaken belief that they will encourage children.

"It is a controversial idea because it is deeply embedded in our society that if we give rewards to our kids we will motivate them," Dr Street said.

"In reality, all the research we have done on motivation shows that as soon as you offer kids a reward to do something, their attention is taken away from what they are doing and put onto the reward.

"Although you might get compliance, by offering a reward, you tend to end up with kids that are less engaged and less motivated to do the things you actually wanted them to do."

While offering a treat is a great strategy to train a pet dog, Dr Street said rewards are only of short term benefit with children, because it doesn't teach them the intrinsic value of learning and behaving well to others.

"We found, looking at kids who were given certificates for reading in year three, that although they might have seemed more compliant then, by the time they got to year six they were far less likely to want to read for fun than a child who was not even reading in year three.

"They had developed no interest in reading, even though they did it for the reward.

"I think we have to think of bigger picture - is it about when our child learns to read or about whether, when they do learn to read, they do that with enjoyment?"

In a 720 ABC Perth facebook discussion parents were divided on the use of rewards.

Amanda It never worked for my kids. Makes things harder in the long run...internal motivation and nurturing helpfulness and empathy is far better in the long term

Chris Different kids are motivated by different things. Find what works and use it. Rewards are great to focus attention on a new skill.

Speaking this week at a schools conference in Perth, Dr Street said often children routinely receive certificates in the classroom and they become meaningless.

"I don't know who they are fooling really," Dr Street said. Rewards for reading won't build a love of reading in children, Dr Street says. ( Flickr: Enokson )

"Every kid in every primary school is fully aware that during the course of the year there will come a point when every child will get a merit certificate for something.

"Are we saying that every child is wonderful, which sort of means that nobody is?

"It is better, if somebody does something well at school, if the teacher can quietly go over to that child and say, genuinely, you did a fantastic job.

"To put a child on a stage in front of the rest of the school and say 'this person is being given this reward because they did what we want them to do in the school' is about power and control, not encouragement to do the right thing."

Dr Street said finding the intrinsic benefits of a task will set them up better for adulthood.

"To celebrate achievement is lovely, but ultimately we want our children to be self directed," she said.

"We want them to find the joy in what they do and not to constantly seek other people's approval.

"To teach our children to constantly look for someone else's approval, whether it is parents or teachers or society, is only setting them up to be fearful in the long run."

Dr Street cites research that suggests reward charts could be doing more harm than good, though it won't be evident in the short term.

"There is a study that shows if parents give stickers on reward charts to their kids for being nice, they are less likely to show empathy and kindness towards each other in the classroom.

"They have learnt to focus on the sticker rather than gaining social skills.

Rather, if they learnt that by sharing their toys their friends would share their toys with them and want to play with them, they will have learnt the intrinsic benefits of being social.

"Because then what happens when you take the rewards away?" Dr Street asked.

"If the child grows up and realises they are not going to get a prize for being nice to somebody, and they don't understand other reasons for social skills and social awareness."