The sidebar displays events, not projects. To get to your projects you go to the Projects Browser where your projects are all displayed as icons. EDIT: To get to the project's media you click on the project's name under the Project Media item at the top of the sidebar. Problem is that only contains media from the open project you are working on.
If you want to save the project's media in the side bar, select the Library name in the sidebar and do File/New Event. A new event will appear in the sidebar bearing its creation date as the name. You can rename it "Beginning Media" or whatever you prefer. Then open your Beginning Media project, not event, and click on the project's name under Project Media at the top of the side bar. The project's media will display in the media browser. Select as a batch all of the media in the media browser, and drag the batch into the newly created "Beginning Media" event. Then, no matter what project you are working on you can pull media from the "Beginning Meda" event in the sidebar.
-- Rich