Howard and Lizzie Sherman, ages 15 and 9, know that they need to complete all their homework and chores in order to receive their weekly allowance. The amount may be a little less than usual if they’ve misbehaved, or a bit larger if they have done some extra work around the house.

When the children want to use their allowance, though, they don’t go to the mall. They turn on the family’s computer or television because there’s a parallel economy in place at the Sherman home, with a currency most often known as “screen time".

The new barter economy: Families “trade among each other in a variety of innovative ways.

They may feel that their children’s time would be better spent reading a book, playing outside or talking directly to another person, according to Richard N. Bromfield, a psychologist on the staff of Harvard Medical School. But for the most part, screen time is seen as acceptable in moderation.

Families dole out the commodity in a variety of ways. Some have their children keep a logbook of time used, or have them “spend" it from a stack of 30-minute allotted “tickets".

Kathleen Dayton of Seattle lets her twin 10-year-olds, and their little brother, age 7, earn extra screen time for minutes spent on extra math drills. “We reinforce things they’re learning in school," she said, “and screen time is a really strong motivator—it makes math happen in my house."

Household chores stay out of the equation, though. Setting the table, unloading the dishwasher and putting away groceries, come with being a family member, Dayton says—“They’re not negotiable." And while she sees the value in doling out screen time, she doesn’t want to overdo it. “Screen time isn’t evil—it’s fine in small doses," she said, “but I feel pretty mixed about giving them much extra."

The American Academy of Paediatrics recommends no more than two hours of screen time a day, and many parents feel that less is better.

Karen Vekasy of Stow, Ohio, said that as her son Mike Bailey “grew out of being sent to his room" at about the age of 11, she found that “electricity"—the family’s name for screen time—was his most valued commodity. “It’s entertainment to him and it’s social because he meets his friends online," she said.

Mike, now 15, earns additional time by assisting his mother with office projects, including PowerPoint presentations and video editing, or helping his grandfather with grocery shopping.

Vekasy also used a reward of extra electricity to encourage Mike to start volunteering at a hospice. “These days, he enjoys going, but without the incentive I don’t think I could have convinced him to try it out."

Sarah Chana Radcliffe, author of Raise Your Kids Without Raising Your Voice, views screen-time allowances as a great motivator for children. She takes a long-term view of it. “Which adjectives do you want your child described as when they are 20?" she asks. “Do you want them, for example, to be known as responsible, respectful, generous and determined? Then start rewarding them for those behaviours from a young age and slowly phase out the rewards as the actions become more automatic."

She tells parents to find a currency that their children care about, such as screen time.

Dayton sympathizes with her son’s desire to check sports scores on the Internet and spend time on a Wii game console. “I read the news online, I do my email," she said. “I like my screen time, too."

A household’s screen-time allowance system may morph over time. A few years ago, the Shermans, who live in Basking Ridge, New Jersey, established the rule that all homework, chores and instrument practice had to be completed before their children were allowed to turn on the television or play a video game. “It made sense in theory, but it turned out the kids would just rush through their work in a slapdash way, to get to the electronics," their mother, Amy Sherman, said. “So we got rid of the week-night time entirely."

The Sherman children have learnt to abide by the system. Howard knows he needs to keep his grades up or he won’t be allowed to join his friends at the local Friday night video game hang-out place. His little sister Lizzie takes care of her real pet dogs before she feeds and pampers her Webkinz, penguins or other online pets.

Bromfield, the author of How to Unspoil Your Child Fast (Basil Books), cautions parents not to overuse household currency systems. Rewarding a child’s good behaviour with toys, points, money or screen time can override the child’s burgeoning sense of self-motivation. “When used too much, rewards can quash a child’s internal desire to do well and do right," Bromfield said. “Then a child’s attitude may turn to: ‘What’s in it for me?’"

As long as screen time or another reward system is part of a larger arsenal of flexible parenting strategies, Bromfield said, it can be very effective.

And parents can aim to use it to their best advantage. Or, as Sherman says: “My son doesn’t ask for more computer time. He asks if he can do the dishes this week."

©2007/The New York Times

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