You may be allowed to use a few popular sources in addition to your top-tier scholarly sources. These newspaper databases will help you locate newspaper and magazine articles and possibly get access to back issues of publications that you wouldn't be able to get through Google. Keep in mind that you'll need to evaluate these sources for credibility as well.
The reference sources below also provide overviews and background information on a topic.
You may also need to consider how to narrow your topic down, or how to relate it back to course themes such as adolescent development. For example, if you're interested in "teen use of social media," maybe you'll want to focus on a specific form of social media such as SnapChat. From there, perhaps you'd focus in how SnapChat, or other new media environments, affect teen relationships.