On Line Project - Involves students enrolling or registering to participate. There may or may not be a fee. Has a specific time limit. Involves periodic tasks the students must do, such as conducting specific research, solving a puzzle, completing a specified activity, or tracking the progress of something. Sometimes involves competition.
Directory is a catalog of sites collected and organized by humans.
Because humans organize the websites in subject directories, you can often find a good starting point if your topic is included. Directories are also useful for finding information on a topic when you don't have a precise idea of what you need. Many large directories include a keyword search option, which usually eliminates the need to work through numerous levels of topics and subtopics. Because directories cover only a small fraction of the pages available on the Web, they are most effective for finding general information on popular or scholarly subjects. . If you are looking for something specific , use a search engine.