I’m currently taking a course on Library Instruction as part of my MLIS work. The following is an exercise I developed for one of my assignments: using tagging to help students think critically about information organization and retrieval. The idea is based on a similar lesson developed by Maggio, Bresnahan, Flynn & Harzbecker (2009) in which they use the concept of tagging to illustrate MeSH. As a premise, both lessons attempt to capitalize on knowledge that students may already possess before the session begins. What do you think? Have you used similar lessons in your instruction sessions? How do you teach students about subject headings?


Grassian & Kaplowitz (2009) suggest that librarians should teach two types of critical thinking: (1) critical thinking about information researching tools and (2) critical thinking about materials received. The following exercise attempts to address the first of these by asking students to reflect upon how information is organized in both formal and informal systems using the popular photo sharing website Flickr and academic databases such as Proquest and Academic OneFile. Maggio, Bresnahan, Flynn & Harzbecker, in their 2009 study, used the concept of social tagging to illustrate the benefits of controlled vocabulary in the MEDLINE database. Based on pre-class and post-class evaluations, the students’ ability to recognize and select MeSH related to a specified article increased from 9.2% to 78.2%. The exercise below is adapted from this case study and utilizes social tagging to improve students’ ability to think critically about database searching and subject classification.

Learning Outcomes

By the end of the instruction session, students should understand how subject headings affect the organization and retrieval of information. Specifically, the following two ACRL Information Literacy Standards apply:

3.2.d: Recognizes the cultural, physical, or other context within which the information was created and understands the impact of context on interpreting the information

2.2.c: Selects controlled vocabulary specific to the discipline or information retrieval source
Students will demonstrate learning through their ability to discuss the social, political, and/or contextual implications of tagging and controlled vocabulary. They will also be able to locate and evaluate subject thesauri in specific databases and compare subject headings between various databases.

Instruction and Activities

Pre-class Prep: Select a number of photos from Flickr that could generate interesting discussions about classification (images from current events, popular landmarks, famous individuals, etc.). Print two copies of each of these images so that there are enough for the expected number of students. Images could also be saved to PC desktops or flash-drives if that is more convenient. Assign two databases to each image that students will use for searching later in the session. Include either a link or a step-by-step guide to navigating to the database homepage.

Social Tagging in Flickr (20 min): Begin the session by briefly discussing the concept of tagging (in case anyone is unfamiliar with the practice) and showing the benefits of searching by assigned tags rather than searching by keyword. Hand out the images printed before class to the students and ask them to assign 3-5 tags to the photo. Have the students find the other person who has their same image and ask them to discuss the tags they chose. Did they choose the same tags? Different ones? Ask 1-2 of the groups to present their findings and, as a class, discuss any biases or assumptions made when assigning certain tags (e.g. perspective, focus, gender, cognitive domain, synonymy).

Locating Database Thesauri (20 min): While still in pairs, have the students find subject headings similar to the tags they assigned using the two databases indicated on their handouts. Ask the students to compare how similar concepts are described in the two different databases (e.g. “Exxon Valdez disaster” vs. “Exxon Valdez oil spill”) and present their findings to the class. Use this time to discuss the biases and assumptions made in assigning subject headings.

Conclusion (10 min): Using Flickr’s website, locate the images that you used for their assignments and show them the actual tags assigned to each image. Discuss any lingering questions about the benefits and drawbacks of using controlled vocabulary to search for articles.


ALA. ACRL. (2000). Information Literacy Competency Standards for Higher Education. Association of College & Research Libraries. Retrieved June 18, 2010, from http://www.ala.org/ala/mgrps/divs/acrl/standards/informationliteracycompetency.cfm

Grassian, E.S. & Kaplowitz, J.R. (2009). Information literacy instruction: theory and practice (2nd ed.). New York: Neal-Schuman Publishers, Inc.

Maggio, L.A., Besnahan, M., Flynn, D.B., & Harzbecker, J. (2009). A case study: using social tagging to engage students in learning Medical Subject Headings. Journal of the Medical Library Association, 97(2), 77-83.