The study, carried out by the Pew Internet & American Life Project from data gathered in 2006, found that 55% of US teens had profiles on social networking sites.
It found that 64% of children aged 12-17 engaged in creating online content, a figure that has risen from 57% in 2004.
Meanwhile, the research found that teenage girls were the most active in blogging, representing 35% of all teen blogs compared with 20% of boys. Pew said the gap had grown between 2004 and 2006 because of increased activity from girls, while older teen girls are the group most likely to blog overall.
Teenage boys were found to be most active on video sites such as YouTube either posting or sharing content, while 57% of teens overall said they watched or shared videos online with friends.
Pew, which produces reports that analyse the impact of the internet on children, families and communities, said teenage boys were twice as likely to post videos online than girls -- 19% of boys do so compared with just 10% of girls.
The full Parent & Teens 2006 Survey can be viewed .