About 20 years ago, Dr. Phyllis A. Katz conducted what has come to be known as the "Baby X" experiment. At a psychology laboratory, adults were introduced to a 3-month-old infant wearing a yellow jumpsuit. Some were told that the child's name was Mary, while others were told that it was Johnny.
There were three toys in the room: a doll, a small football and a gender-neutral toy. The adults who thought they were with a girl tended to offer the baby the doll. Those who thought they were with a boy were more likely to use the football.
"We found exactly the same thing when we did it again in the mid-1980s," said Dr. Katz, who is the director of the Institute for Research on Social Problems in Boulder, Colo. She said the results show that adults, often without thinking about it, use toys to convey gender-specific expectations.
If you would like to expand the types of toys your children play with, and the ways they play with those toys, here are some things to bear in mind:
"The easiest way to get children to play with anything is for an adult to sit and play with them," said Dr. Jeffrey L. Derevensky, who is an associate professor of educational psychology at McGill University in Montreal.
Parents often underestimate how much their children value their individual attention. If you want your child to try building a model or drawing instead of playing a video game, offer to do those activities with him.
Pay close attention to the toy commercials your children see.
Toy commercials have a profound influence on young children, who tend to view them uncritically.
"In the 1970s, about 80 percent of toy advertising was aimed at parents," said Dr. Brian Sutton-Smith, a professor of education at the University of Pennsylvania, who studies how children play. "Today, about 80 percent is aimed directly at children."
Talk to your children about why they think a particular toy would be fun, or why they wouldn't want to play with it.
Remember that toys are part of a larger social setting.
Children who watch toy commercials pay close attention not only to the product but also to the social or family situation in which the toy is shown. "The child may assume that if she gets the game, everyone in the family will sit down and play with her," Dr. Derevensky said.
"But her parents may buy the game in the hope that she'll spend more time amusing herself or playing with other children."