In the context of new media, teenagers are considered as active consumers and producers of digital information because in their use of new technology, teenagers make their own meanings, develop their own understandings, and interact within online communities. The impact and social implications of new media in teens' everyday life raises important questions regarding teens' social development, social learning, identity creation and purposeful creativity. Although ethnographic work has documented youth participation in various online spaces, teen YouTubers' ongoing participation in sharing videos on YouTube has not received great attention. This study was initiated in response to the prevailing lack of research evidence of teens' use of YouTube. The research problem in this study addressed teens' participation on YouTube, and understanding the impact of YouTube on teenagers, in particular the ways in which they construct and present different identities. This study centred on three research questions that identified common video categories uploaded by teenagers; recognised motivating factors behind ongoing teen participation in video sharing; and, examined the ways teenagers constructed and presented their identity in their video design, production and distribution through YouTube. A netnographic approach was used to probe teen experiences through their participation in YouTube video sharing. The significant factors for teen YouTubers' ongoing video sharing included personal, social learning, and community factors. These results show how specific categories of video are associated with teens' time use, interest, motivation and identity. In addition, the videos showed the context of social e-learning, teen creativity and productivity, elements of new media participatory culture, and reinforcement of teens' claimed affinity spaces. The overall findings of this study highlighted that when teen YouTube engagement is interest-driven, teens' participation in sharing videos on YouTube becomes more meaningful and purposeful, and teen YouTuber identity is constructed and presented.