When given attention by adults, the time they spend playing doubles. Boys laugh and tease more. See also developmental stages in the instructors' notes. One boy is different than two boys. Boys in all-female worlds, asked to do things they're not developmentally ready to do, get frustrated.
Boys try to establish power and increase status in group, girls tend to avoid conflict.
For girls, essence of a friendship is talk, for boys the essence of friendship is doing, and boasting and threatening and competition. Be careful not to judge boys by female standards. This can often be a concern in schools, which are more often taught by women. Sometimes it's best to talk to boys in five words or less, and to combine the words with actions. For boys, solving the problem fixes the emotion.