This study examines the effects of increasing the cost of social interactions and food on overweight and non-overweight youth. Using a computerized operant task youth will earn points exchangeable for food and social activity.

The investigators predict that both overweight and non-overweight children will substitute food for interactions with an unfamiliar peer when this alternative is made expensive. Also, the investigators predict that both overweight and lean participants will defend their choice to spend time with a friend even when this alternative is made expensive.

Inclusion Criteria:

• Boys and girls ages 9-11
• Children must have a BMI equal to or greater than 15th percentile for their age
• Children must report at least a moderate liking of the study foods

Exclusion Criteria:

• Children should not have any food allergies
• Children should not have any dietary restraint
• Children should not a cold or upper respiratory distress
• Children should not have any psychopathology
• Children should not have any developmental disabilities
• Children should not be taking any medications that could influence their sense of smell and taste and activity level

Boys and girls ages 9-11.