The best way to organize entries by multiple authors on the same topics is to use EdBlogs categories feature.
Categories provide a method to label and bundle posts together. Only Editors and Administrators may create and edit categories, while all users may use categories to label posts with applicable topics. Categories have the functionality to be hierarchical to create complex relations between topics.
Tags are similar to categories in EdBlogs in that they are used to label and organize posts. Unlike categories, tags may be created by any user that can draft a post and tags are not hierarchical.
In order to use categories to organize your blog with multiple authors, create a category for each topic. To do this, sign into the Dashboard of your blog. Then click on the Posts pane. From the expanded menu, select Categories. Complete the page provided and click Add Category. Repeat as necessary to create additional categories for you authors to choose from. All categories you add through this interface may be accessible by all authors in the Add New Post and Edit Post environment.
Once you have added all Category topics, invite each author to check the appropriate categories for each post he or she writes. It is also possible to edit existing posts to add categories. As each author write posts and categorize over time, posts with similar topics may be accessed by clicking on the category of choice.