Podcasts (digital audio files) can be utilized creatively to supplement classroom learning. They can be both easily created by instructors and conveniently accessed by students. Students are very receptive to the use of this type of technology as a way to reinforce conceptual understanding of course material. An activity combining a podcast with an active-learning worksheet references the literary classic "The Lord of the Rings" as an analogy to help students understand the many proteins, cells, and processes involved in the human immune response. This activity has helped a significant number of students improve their understanding of this subject.
Digital audio files, more commonly known as podcasts, have become popular tools in education. Podcasting is a rapidly growing technology that most teenagers and college-age students use with ease. With very little technical knowledge or financial investment, one can create single, easily downloadable audio files. Series of podcasts that listeners can automatically subscribe to (known as RSS feeds) are also becoming commonplace. More and more educators are tapping this resource as they realize the value of this unique and flexible mode of communication. In fact, just recently my daughter came home and announced to me that her second grade class had just recorded and posted their original poetry as podcasts on the Internet!
Many excellent podcasts currently exist that support the science of biology. Sources range from governmental agencies such as the Centers for Disease Control (http://www2a.cdc.gov/podcasts/) to media outlets such as The New York Times (http://www.nytimes.com/services/xml/rss/nyt/podcasts/scienceupdate.xml). ITunes, the free software that supports digital video and audio files for the iPod and iPhone, now includes a wonderful resource for podcast enthusiasts. The "iTunesU" feature, found in the iTunes Store, presents university-level multimedia material from a variety of disciplines (Young, 2007). Through this portal, one can be a "virtual" student at M.I.T. by accessing audio and/or video lectures from Human Genome Project pioneer Eric Lander or renowned cancer researcher Bob Weinberg. Yale and Stanford University also post biology-related course content, and the University of Arizona has a terrific "Ask a Biologist" series. Podcasts are also now associated with leading journals such as Science (http://www.sciencemag.org/multimedia/podcast/).
The use of podcasts (and videocasts) as an alternative to delivering classroom lectures in person has gained mixed reviews. Critics cite the huge size of the audio files (for 50-75 minute lectures) and lack of interaction with students as the two biggest problems associated with their use in an educational setting. Advantages of these formats include the ability to create educational materials customized to one's lectures and bridging the technological "generation gap" between instructor and students. Podcasts also provide a creative way to educate students in large-enrollment college courses. Perhaps the biggest advantage lies in a student's ability to access podcasts easily and flexibly, fitting them into their busy schedule when they have time (Jensen, 2007). Students are even being encouraged to create podcasts as an output for student research projects in certain disciplines (Vatovec & Balser, 2009).
A Mini "How to Podcast" Guide
Besides a computer, the only monetary investment needed to produce a podcast is a headset with a microphone. These vary in price, but I have found a simple USB headset with microphone priced just under $30 to be perfectly sufficient. I have experimented with two types of software to create my podcasts. QuickTime Pro (a version of QuickTime with more functionality that can be purchased at a minimal cost) can easily record audio files and save them in the correct format (mp3 file) with minimal technical expertise. A free sound-editing program called Audacity (http://audacity.sourceforge.net/) can also be used effectively and gives a podcaster more editing power than QuickTime Pro. I have posted several versions of a podcast on the Internet produced by both of these types of software (http://www.biologymom.com/podcasts) as examples.
Researching and developing a creative podcasting idea, writing and rehearsing a straightforward script, and speaking clearly and slowly are all key to making a podcast coherent and engaging (Villano, 2008). A few good references that also help beginning podcasters are included here (Flanagan & Calandra, 2005; Mikat et al., 2007). Mp3 files can be easily uploaded to and downloaded from course management systems like Blackboard or an educator's personal website. Students do not need a portable mp3 player, as they can listen to the podcasts directly from a computer. Most types of standard, commercially available audio/video software (Windows Media Player, QuickTime, RealPlayer) will play these files automatically.
While I personally have not worked with one, portable digital audio recorders exist that can be adapted to this purpose. More experienced podcasters can also look into creating RSS feeds if they plan to have multiple podcast episodes for listeners to tune into regularly (Griffey, 2007). If listening to the podcast is required as part of a course, I would recommend posting the podcast script as a pdf file so that the students can read the material covered, if necessary.
Developing a Podcast & Worksheet Activity on the Immune System
It is my personal belief that podcasts cannot really replace personal, face-to-face interaction between educator and student in a learning environment. I set out to discover whether brief (<15 minute) podcasts could be effective, however, when used to supplement or enhance the curriculum in my courses. So far, I have used podcasts to highlight exciting and innovative developments in the field of biology for students in my college-level introductory biology courses and labs.
I first piloted this idea with an original podcast entitled "Cloning Extinct Species: Fact or Science Fiction" that described the cloning methods and biotechnology referenced in movies such as "Jurassic Park" and "The Island." The podcast was offered to students in my lecture courses as an optional exercise to listen to outside of class. Many students listened to the podcast (172 out of 221 [78%] responding to an anonymous survey) despite its not being required. Of the 172 students who listened to it, 142 (83%) felt that the podcast enhanced their understanding of the subject of cloning. This helped to establish the willingness of students to access this type of technology as well as demonstrate a very positive (but subjective) perception of its educational usefulness. I then searched for more sources of inspiration for podcasts that would help explain some of the typically challenging concepts that I cover in my courses each year. One of those sources of inspiration came from an unlikely place.
I remember reading The Lord of the Rings trilogy by J. R. R. Tolkien several times during childhood, each time enjoying the intricate storylines and imaginative characters even more. I remember having to refer to maps and character genealogies often because of the story's complexity. So it will come as no surprise that my inner science-fiction geek was thrilled to come across a YouTube video in 2006 (http://www.youtube.com/watch?v=zyJpNvI0bt0&feature=channel_page) that attempted to use The Lord of the Rings as an analogy for the immune system. I clarified and expanded on this idea in order to create a podcast and active-learning worksheet as an activity in our introductory college-level "Biology of Organisms" (Bio152) lab. This audio file (available at http://www.biologymom.com/podcasts) and worksheet entitled "Lord of the Immune System" uses stories and characters from this fantasy epic as a way to better understand the complex workings of various parts of the human immune system. I set out to discover whether this activity would help students grasp this subject more clearly.
Assessing the Activity
The podcast engages students in the analogy while presenting a framework for the concepts associated with the immune system. This is done by associating different types of cells with different heroes or villains from the Lord of the Rings story. The active-learning worksheet is a study tool to help students visualize and apply the ideas presented in the podcast effectively. Specific review questions help students go into more depth in the subject matter, beyond what can be explained in a brief podcast.
Students were first introduced to this podcast during the spring 2008 semester. All students had access and could listen to the podcast regardless of whether they owned an mp3 player, as they could listen to the podcast directly from the Blackboard course interface as well as transfer and listen to the file on a portable mp3 player (e.g., iPod). Listening to the podcast was optional; however, students in all eleven BIO152 lab sections were given two podcast-related extra-credit questions on one of their lab quizzes as an incentive to listen to it. Thirty-three percent of students in BIO152 (141 out of 431 students) accessed the podcast (Blackboard statistics tracker) despite it being optional. I then decided to design a complementary active-learning worksheet (Figure 1) in order to reinforce concepts and go into a little more depth in the subject matter.
During the spring 2010 semester, the podcast and associated worksheet were used as an extra-credit activity in the BIO152 laboratory setting. When students arrived to lab, they had already learned about the immune system in the lecture component of this course. They were given a short, timed (10 minute) pop quiz to assess their understanding of the various components of the immune system. The quiz consisted of 27 fill-in-the-blank questions with a list of answers that had to be used at least once, but could be used more than once. This made the quiz challenging, but it was designed to reduce the incidence of guessing. The quiz was reviewed by my colleague who teaches the lecture portion of the course to ensure that it correlated well with what was covered in lecture. After the quiz, the worksheet was distributed to each student and the podcast was played for them through the lab speaker system. The students were given ~20 minutes to discuss the worksheet in small groups (3 to 4 students) and answer the questions. They were unaware that they were going to be given the same timed quiz (with answers mixed up) after the activity in order to determine whether there was an improvement in their understanding of the immune system.
Pre- and post-podcast quizzes from the 74 students who participated in this activity were analyzed. Sixty-eight of these students (92%) improved their quiz score as a result of doing this activity. Point gains ranged from 1 to 18 points, with an average of 6.4 points. Three students had no score change, and another three students did slightly poorer on the quiz after the activity was completed. Figure 2 shows the distribution of quiz scores before and after the activity was performed. Thirty-three students were familiar with the Lord of the Rings story, having either read the books or seen the movies. These students had an average point gain of 7.3, whereas students who were not familiar with the story increased their score by an average of 5.7 points.
The other instructors and I circulated around the lab during discussions, in order to answer questions and make sure that the students were progressing in their understanding of the immune system. I also collected the worksheet to evaluate the students' responses to the review questions. Most of the students did a good job of following the analogy and completing the questions correctly, regardless of whether they were familiar with the story or not. They all seemed to benefit from working in small discussion groups, although the activity could certainly be done on an individual basis. Students who had either read the books or seen the movies were quite clever when it came to the review question asking them to fit vaccination or drug therapy into the story. A couple of students likened the magical, protective chainmail worn by a main character (Frodo) to vaccination. Other students thought that capturing one of the bad guys, bringing it into the fortress, and figuring out its fatal weakness would be a good analogy, as would tapping into the expertise of a hero who had already fought and defeated the enemy. Drug therapy was also creatively added to the story by students who compared it to a battalion of elf warriors who come from far away to help the protagonists fight the villains. A student who was not familiar with the story suggested that vaccination would be like advanced training for soldiers. Another student commented to me that they were inspired by this activity to try to use the movie "Star Wars" as an analogy to help them study for the next midterm exam. Despite seeing a significant point gain even with students who were not familiar with the Lord of the Rings story, I have created an alternative worksheet (Figure 3) for students who may be more comfortable with a different analogy after listening to the podcast. Instructors can also develop their own podcasts based on some sort of battle analogy. The battles from the movie "Avatar," as well as the "Harry Potter" and "Twilight" movies, could all be adapted to this model. While this may not be realistic for courses with large enrollments or labs, students can also create their own original podcasts in a variation on this activity (see Vatovec & Balser, 2009) using different analogies that they expand upon.
In addition to the cloning and immune-system podcasts already mentioned, I have another podcast/worksheet activity based on gene expression that was performed in a lecture course (enrollment 450 students) with objective assessment data, which was also very successful (currently submitted for peer review). It is my hope that the example presented in detail here will encourage instructors to develop their own short, creative podcasts. While I chose to focus on a few key topics that my students tend to struggle with, instructors can easily produce podcasts throughout their courses on any number of topics.
The "Lord of the Immune System" activity helped the great majority of students in this course to make significant gains in understanding this complex aspect of human physiology. The podcast served as a novel way to draw students into the subject matter, while the worksheets help them to actively and flexibly explore the topic in more depth. When used in a thoughtful and balanced way, podcasts have the power to enhance biology curricula as well as bridge the generation gap between instructors and students. A very small time investment and a little creativity on our part as instructors can yield great results, encouraging our students to use their time outside of the classroom to deepen their understanding of the material covered within.
I am grateful to my students – especially the entering classes of 2007 and 2009.