We tested the hypothesis that 4 - 5-year-old girls and boys in same-sex problem-solving groups would perform equally well when the group task required various cooperative and self-serving behaviors to obtain a resource. The hypothesis that girls and boys would employ different behaviors to obtain the resource was also tested. 20 same-sex, same-age groups of 4 children each (10 groups of girls and 10 groups of boys) were videotaped while solving a problem involving a cartoon movie as a resource. 1 child could view the movie provided 2 other children helped, 1 to turn a crank and 1 to push a light button; the fourth child was relegated to a bystander position. Results revealed that girls and boys were equally effective in achieving viewing time; gender variance in viewing time was significantly greater for girls than for boys; girls and boys did not differ in total behavioral output, but girls tended to use more verbal behavior than boys and boys engaged in significantly more physical behavior than girls; affect in boy groups was more positive than in girl groups; girls who achieved the most viewing time within their group differed behaviorally from girls who achieved the least viewing time, but did not differ behaviorally from boys; boys who achieved the most viewing time did not differ behaviorally from boys who achieved the least viewing time.