This website from the University of Maryland's National Foreign Language Center offers some pretty neat brief online supplementary readings and multimedia resources (my personal favorite: "a song to the tune of Turkey in the Straw that contains a number of commonly used exclamations indicating surprise and dismay.")
It is geared toward the high school level, but could also be used for college students or independent learners. All the resources are organized by topic and experience level, and each reading also includes online activities to practice comprehension, vocabulary, etc.
In simplified characters: http://www.nflc.org/projects/current_projects/used_chinese_los/simplified_list.html
In traditional characters: http://www.nflc.org/projects/current_projects/used_chinese_los/full_form_list.html
-Laurel, Cheng & Tsui Editorial Department