Put Some Movie Wow! in Your Chemistry Teaching - ACS Publications

Jul 12, 2012 - with popular actors, incredible sets, memorable dialog, and special chemical effects would be ... scrubbers, rocket fuel comparisons, m...
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Put Some Movie Wow! in Your Chemistry Teaching Christopher A. Frey, Marjorie L. Mikasen, and Mark A. Griep* Department of Chemistry, University of NebraskaLincoln, Lincoln, Nebraska 68588-0304, United States S Supporting Information *

ABSTRACT: Movies and movie clips have been used by many instructors to teach chemistry. Entire movies based on true chemical stories are used because they provide students with a common experience after which instructors can launch writing lessons about the chemistry, the scientists, or engineers, or even postscripts to the story presented in the film. In contrast, movie clips are used to animate a chemical topic during lecture in a way that grabs student attention. This gives students a strong anchor upon which they can contextualize the rest of the lesson. To find the most pedagogically useful clips, we formulated a hypothesis that clips with popular actors, incredible sets, memorable dialog, and special chemical effects would be the most useful for instruction because they would have the strongest anchoring capacity. That is, clips with more Wow! should be more useful for teaching and learning. The results of our study establish a set of criteria for choosing clips from feature films that chemistry instructors can use to grab the student attention and maximize learning. KEYWORDS: Elementary/Middle School Science, High School/Introductory Chemistry, First-Year Undergraduate/General, Multimedia-Based Learning, Drugs/Pharmaceuticals, Forensic Chemistry, Professional Development, Nonmajor Courses Bullet (1940) or Me & Isaac Newton (1999) as source material instead of newspaper articles.9 In that same paper, we describe 10 other similarly useful movies, each with different chemical and social themes. One of the earliest examples of using movie clips to teach science was when the opening 14 min of Raiders of the Lost Ark (1981) was shown to middle school science students to teach science in the context of a lesson plan about South American exploration.10 Among the many encounters in that clip, Indiana Jones replaces a bag of gold with a similarly sized bag of sand. Students learn to estimate the volume of the bag and then calculate the mass of that much gold and sand, using the concept of density (sand is about 2.5 g/cm3 and gold is 19.3 g/ cm 3 ). Students who watched the clip had improved comprehension, ability to utilize the information, and longterm recall of facts compared to students who only studied the content. The engaging clip gave students a way to contextualize the new information.11 It allowed them to connect new facts to the clip and to their prior knowledge. A recent meta-analysis of 26 studies showed students assimilated information better when learning was connected to animated images than when the images were static.12 The largest positive effects occurred when movie clips were used. The first explicitly chemical list of movie clips was assembled in 2001.13 Seven movie clips were connected to general chemistry topics and separated into three themes: chemicals that threaten, chemicals that save, and chemical learning and reasoning. More recently, we identified dozens of movie clips, separated them into 10 distinct themes encompassing the entire history of the movies, and provided explanations about the real

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n effective way to transform content into knowledge that students can use in new contexts is to anchor it to things they already know.1 Anchoring is necessary because the cognitive load perspective postulates working memory is limited, making it difficult for learners to process too many ideas at once.2 One effective way to anchor student knowledge is to connect it to their extensive familiarity with movies. Movies and television shows have been used to teach all fields of science. The earliest extensive guidelines for using movies to teach science were described in Science in Cinema,3 a book that focused on science fiction films to teach scientific principles in a nonscience-majors physics course. This book was updated as Fantastic Voyages4 and expanded to include data showing that student attitudes, content knowledge, and problem-solving skills were all improved when students watched science fiction films. Since then, the list of entire movies suitable for teaching chemistry has been growing. Movies based on true chemical stories have proven to be especially useful. Apollo 13 (1995) and October Sky (1999) have been identified for their ability to drive discussions about lithium hydroxide carbon dioxide scrubbers, rocket fuel comparisons, model rocket propellants, payload calculations, and persistence of effort in the face of setbacks.5,6 Jurassic Park (1993) was used to drive discussions about cloning, protein structure, DNA structure, molecular biology, and scientific ethics.7 The orphan-disease movie Lorenzo’s Oil (1992) provides students with enough context to promote deep explorations of the ethics of clinical trials, doctor−patient interactions, and persistence in the face of insurmountable odds.8 In our own research, we found general chemistry students were more motivated to write 600-word reports and did a better job when we used Dr. Ehrlich’s Magic © 2012 American Chemical Society and Division of Chemical Education, Inc.

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chemistry behind the clips.14 Half the movies showed the dark side of chemistry: Jekyll and Hyde, invisible man chemistry, chemical weapons, malevalent chemical companies, and drug addiction. These are equally balanced by the movies showing chemistry’s bright side: chemist inventors of oxymoronic products, forensic chemists, chemistry teachers and professors, good research chemists, and drug discovery. Finally, it has been established that student perceptions of science and scientists are strongly driven by out-of-school forces such as movies and television cartoons, sitcoms, and dramas.15 Notably, the origins of the “mad scientist” stereotype was traced to 18th century chemists16,17 by an analysis of the most persistent results of the Draw-A-Scientist-Test in which students are asked to draw a scientist without any prior prompting. The dominant drawing is someone wearing a lab coat and glasses while holding a test tube. That is, the mad scientist is most often a chemist, or a physician performing a chemical analysis, with Einstein’s hair. Even though students are increasingly drawing more diverse scientists, another important reason to use movie clips in the classroom is to create a formal environment in which to respond to the persistent images of scientists in popular culture.

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IDENTIFYING THE WOW! During our decade-long search for movie clips, we discovered over 100 movies with chemical scenes that appear to be suitable for teaching chemistry both in and out of the classroom.14 We have incorporated dozens of movie clips into public outreach lectures and about 10 clips in a liberal arts chemistry course. The clips used in the classroom are chosen primarily for the type of chemistry portrayed in them, rather than for their movie appeal. On the other hand, it would not be worth the effort to use a dull movie clip from a boring movie so there was some preselection to identify the initial set of 50 clips. The ratings of over 50 clips by the experts indicated a strong positive correlation between Wow! and pedagogical utility (Figure 1). Twelve clips fall into the “low wow, low utility”



METHODOLOGY To find the most pedagogically useful movie clips, we formulated a hypothesis that clips with popular actors, incredible sets, memorable dialogue, and special chemical effects would be most useful for instruction because they would have the strongest capacity for anchoring the lesson. That is, clips with more “Wow!” should be more useful for teaching and learning. Conversely, movie clips with fewer of those features will be less useful. During the first phase of the project, over 50 clips were rated by 11 high school chemistry teachers during a summer professional development course (see Table 1 in the Supporting Information for a full list of the movies and ratings). This exercise created the master list from which clips were selected for use in the second and third phases. These chemistry teachers were considered ratings experts. During four of the five days of the course, they spent mornings discussing the literature about choosing material for the chemistry curriculum and the use of engaging lecture materials, then spent time with some hands-on activities, returned from lunch for a shorter discussion about a variety of topics, and finally rated 12−14 movie clips. During the second phase of the project, about 50 summer camp students rated 11 movie clips in a 1-h period. In the third and final phase of the project, about 50 middle and high school science teachers rated five movie clips in a half-hour period. During all three phases, the participants would watch a clip and then rate it for Wow!. Each clip was followed by a short lecture about the chemistry in the clip, after which the teachers rated the “pedagogical utility” and students were asked to rate “how much chemistry did you learn?” We had several expectations going into the project: teachers and students would perceive the Wow! and utility and learning differently; teachers would rate clips containing profanity as having low pedagogical utility; and movies in black and white would seem outdated to students and have lower Wow!. Within our final selection of clips, therefore, we included examples with high and low Wow!, high and low utility, and modest cursing. By including clips with parameter extremes, we were able to explore the correlation between teacher and student responses.

Figure 1. Quadrant analysis of the movie Wow! versus pedagogical utility for over 40 movie clips shown to 11 high school chemistry teachers. Both factors were rated from 1 to 5, where 5 is highest. See Table 1 in the Supporting Information for a list of the movie titles and ratings.

quadrant and showed the most linear correlation between the two factors. Even though one might predict these lowestranked clips should be avoided in the classroom, we still use The Devil-Doll (1936) with Wow! of 2.2 and utility of 2.5. In the clip, the characters discuss atomic structure as part of a project to shrink animals and humans to one-sixth their normal size so there will be enough food for everyone. It is useful for sparking a discussion as to why atoms cannot be shrunk, a question that can stump even the best educated chemists when stated from this nonacademic angle. Alas, the mad scientist’s project is doomed to failure because the food atoms will be a different size from the human and animal atoms. Seven clips fall into the “low wow, high utility” quadrant but all of them have at least modest Wow!. The dynamism of moving pictures practically guarantees any given scene will have some visual interest. For instance, a clip with the lowest Wow! but highest utility would be considered purely informational 1139

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Figure 2. The relationship between Wow! and pedagogical utility versus (A) movie release year and (B) Internet Movie Database (IMDB) rating for over 40 movie clips shown to 11 high school chemistry teachers. Two silent movies released before 1936 were omitted from panel A to avoid skewing the results. Even though IMDB ratings can range from 1 to 10, our set were in the range of 4.6 to 8.7. See Table 1 in the Supporting Information for a list of the movie titles and ratings.

Table 1. Movie Clips Shown to Both Students and Teachers Movie (Year)

MPAA Ratinga

Genre

Clip Summary

Harry Potter and the Chamber of Secrets (2002) Senseless (1998)

Adventure, family, fantasy Comedy, romance

PG for scary moments, some creature violence and mild language R for language and sexual content

Fuller Brush Girl (1950) Fuelin’ Around (1949) Men in Black II (2002)

Comedy Comedy, short Action, comedy, sci-fi

Unrated Unrated PG-13 for sci-fi action violence and some provocative humor

Repotting mandrakes Human clinical drug trial side effects Chemical set elements Special effects Alienicide leaves phosphorus residue

a

The MPAA rating system was created in 1968 as a consumer guide to movies shown in the United States; it has no legal standing. PG means Parental Guidance Suggested; Some Material May Not Be Suitable For Children. PG-13 means Parents Strongly Cautioned; Some Material May Be Inappropriate For Children Under 13. R means Restricted; Children Under 17 Require Accompanying Parent or Adult Guardian. Between 1930 and 1968, the so-called “Hays Code” ensured that studio-produced movies adhered to a fairly strict set of censorship guidelines.

but no clips are in that furthest corner. An example of a clip in this quadrant is Madame Curie (1943) with a Wow! of 2.5 and utility of 4.0. In that clip, the action takes place in a darkened room while Marie Curie places powdered samples of pitchblende, uranium, and thorium in a radiometer and then reads the values to Pierre. They are confused why the pure uranium and thorium samples only account for half the readings of the ore. Marie then reads a list of pitchblende components, ponders the last line that says “Other extraneous material” for a short while, and finally raises her head. There are two other information-heavy scenes in the movie. All three efficiently communicate the scientific question being pursued at that moment. Nine clips fall into the “high wow, low utility” quadrant. These clips might be criticized for having more entertainment than educational value except that most of them hug the midrange utility values. One example would be The AbsentMinded Professor (1961) with Wow! of 3.4 and utility of 2.4. In the clip, chemistry professor Ned Brainard cranks up the electrically charged bubbling apparatus located in his garage. There are chemical and mathematical formulas on a blackboard and in his notebook. He realizes he had the sign wrong in his

mathematical equation and concludes he can increase the voltage without worrying about “throwing off a little hydrogen”. The postclip chemical explanation describes his equation and the butadiene chemical structure in his notebook to provide an explanation for the flying rubber he invents. Twenty-seven clips fall into the desirable “high wow, high utility” quadrant. These clips with higher than the midrange values in both categories are all useful for teaching chemistry. The highest rated clip is Apollo 13 (1995; Wow = 4.9, Utility = 4.8) and it is stimulating on many levels. It has a based-on-atrue, patriotic, can-do story in which characters work under pressure of possible death as they talk of CO2 panel lights, lithium hydroxide canisters, breathing deadly carbon dioxide, and carbon dioxide scrubbers. To test whether Wow! and utility are related to whether the clip was in black-and-white or color, we plotted those ratings versus each film’s release year (Figure 2A). Because there was no significant correlation for either rating with the movie release year, we concluded the color and age of the movie clip did not matter. To test whether it was possible to predict whether a clip will have high Wow! based on the quality of the entire movie, we plotted both ratings versus the movie’s rating 1140

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on the Internet Movie Database (Figure 2B) because it is based on hundreds of thousands of viewer responses. There was no significant correlation, indicating movie quality cannot predict Wow! or pedagogical utility.



CHOOSING THE CLIPSWITH CAUTION During the second and third phases of the project, the same five movie clips were shown to young people and teachers. The young people were participating in a series of science summer camps hosted by the University of NebraskaLincoln and the Nebraska EPSCoR (Experimental Program to Stimulate Competitive Research). The two goals are for students to learn science through doing science and to explore the intersection of science, technology, and society. Our “Chemistry in the Movies” presentation helped them meet the second goal. Each of the four hour-long presentations with 11 clips was attended by 10−15 middle and high school students. The middle and high school teachers were participating in a morning-long professional development workshop (Table 1) hosted by the University of NebraskaLincoln Center for Science, Math, and Computer Education. We gave our “Chemistry in the Movies” during two of the three 30-min sessions during which 25−30 teachers rated five movie clips. The clips shown to both students and teachers were chosen to explore the range of responses to Wow!, Utility and Learning, black-and-white versus color movies, and the role of profanity. For instance, the clip with the highest Wow! according to the rating experts was the mandrake repotting scene from Harry Potter and the Chamber of Secrets (2002). The clip with the highest pedagogical utility was the scene from Fuller Brush Girl (1950) in which little Henry says he tested some of the cream wave lotion in his chemical set. It was not any good so he poured it back into the dish, which was later applied to his mother’s hair. When asked what he added, he names one-fourth of the periodic table, including argon, thorium, and polonium. No wonder she is bald! Two clips were in black and white: Fuller Brush Girl (1950) and the Three Stooges short Fuelin’ Around (1949). Finally, the scene from Senseless (1998) includes a mention of the drug’s possible side effects including rectal itching and rectal burning. The word “rectal” is not profane but is used for its shock value. The movie rating system created by the Motion Picture Association of America (MPAA) is a useful guide to the violence, sexual themes, and profanity that may be presented in movies (Table 1). The ratings for all movies can be found at either the MPAA Web site18 or on the IMDB Web site.19 Although our project did not favor movies emphasizing themes with more stringent ratings, some movies with violent themes or profanity (i.e., The Bone Collector; Senseless; Apollo 13) were included in the larger samples. On balance, the authors feel these clips have value as teaching tools. Nevertheless, teachers should review the movie content themselves before introducing it into the classroom to decide whether it is age and circumstance appropriate for their students. A side-by-side comparison of students and teachers ratings for five key movie clips (Figure 3) shows high agreement of student perception of learning with teacher perception of pedagogical utility for all five movies. Students and teachers perceive chemical instruction similarly. The highest rated clip by both groups was Harry Potter and Chamber of Secrets (2002), indicating both found it was valuable to learn about alcoholic mandrake extracts and the structure and properties of atropine and scopolamine. These esoteric chemical topics are presented

Figure 3. (A) Wow! and (B) pedagogical utility or chemistry learning for the five movie clips shown to students and high school chemistry teachers. Each group was asked to rate both factors from 1 to 5, where 5 is highest. There were 53 students who heard the presentation as part of four summer camps and 50 middle and high school teachers who heard the presentation as part of two presentations at a day-long professional development workshop.

in the context of “where do molecules come from?” and how even a small structural difference can cause significantly different physiological effects. The lowest rated clip by both groups was Senseless (1998). The postclip explanation concerned human clinic drug trials and the purpose of informed consent. We had expected the teachers to give this a low rating because of the word “rectal” but we did not expect youths to give it a low rating. Therefore, an alternate explanation for the common low rating was that both groups may consider informed consent and drug side effects to have a weak connection to chemistry. Teachers and students differed more in their perception of the Wow! The single clip rated more highly by teachers was Harry Potter and Chamber of Secrets. This is always the first clip we show and we begin by asking who has seen the movie. Nearly all the youths have seen it and some call out they have seen it multiple times or someone will say he or she loves Harry Potter. Most but not all the teachers have seen the clip. Adults are more likely to have seen the clip once years ago and are perhaps more impressed seeing the scene with fresh eyes during our presentation. In contrast, students rated three clips more highly than teachers: Fuller Brush Girl, Fuelin’ Around, and Men in Black II. As two of these clips are in black and white, it debunked our expectation that such films would not be favorably received. In fact, the difference was strongest for the Three Stooges short. Prior to the Fuelin’ Around clip, we always ask who has heard of The Three Stooges and have been surprised to see youths claim enthusiastic acquaintance with the 1141

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and pedagogical utility do not correlate with IMDB ratings for the entire movie or with the year the movie was released. Therefore, when movie clips are used to teach chemistry, their effect is independent of the entire movie, whether the movie is in black-and-white or in color, whether it has profanity or shocking language, and whether it has cartoon violence. Students are as adept as teachers in identifying whether an explanation conveys chemical knowledge but the two differ somewhat in their perception of movie Wow! This is acceptable from the point of view of the instructor because he or she will choose a clip primarily for its ability to teach a chemical concept and secondarily for its Wow! This also suggests there is not a pressing need to continually identify clips from the latest feature films. Instead, it is better to focus one’s effort toward developing lesson plans that use the contextualizing power of movie clips known to have pedagogically useful scenes. The best clips will generate interesting problems and situations for students to explore. One finding worth considering further was that student reaction to a clip can be more sophisticated than expected. The students in our sample gave a surprisingly nuanced reading of the violent action presented in Fuelin’ Around. Their response to the chemistry lab shenanigans in this decades-old Three Stooges short suggests they read cartoon violence in a different way from movie realism. They do not see the actors coming to any harm or that the scenario could actually happen. If an instructor can accept the goofiness it represents, it is possible to turn it into a deep learning moment by asking “how would you do that special effect?” rather than focusing on the numerous safety violations.

violent comedians. Perhaps teachers give it a lower Wow! because they are more familiar with the trio from their own childhoods. They may negatively associate the Stooges with the repetitiveness of conked heads rather than with a unique genre of anarchic comedy. Fuelin’ Around was selected to test the effect of the postclip explanation on “how much chemistry did you learn?” (Figure 4). In the clip, the Stooges are being held prisoner until they

Figure 4. Effect of the postclip explanation on student responses to the question “How much chemistry did you learn?” for Fuelin’ Around. There were 26 students who heard the presentation of the postclip admonition about safety and 27 students with the postclip group discussion about special effects. The rating was from 1 to 5, where 5 is highest.



develop a rocket fuel. To start, Shemp adds pyrogallic acid to the main bottle and it starts bubblingthe first special chemical effect. Moe tells him to add more stuff. As he reaches for a bottle on the top shelf, a jug falls onto Shemp’s head. Dazed, he pours the solution into Moe’s sleeve. Moe bonks Shemp in the head, causing Shemp to knock over the main bottle. The solution causes sparks as it runs across the table the second special chemical effect. Moe decides it is strong enough and corks it only to have the cork turn into a projectile that hits their captor in his unmonocled eye. The postclip “safety” explanation was to say it demonstrates why you need to pay attention to lab safety. The student perception of learning under this condition shows an almost even distribution of responses from 1 to 5. Such a distribution suggests that a dull explanation will receive an average score of about 3. The “special effects” postclip discussion asked students how they might create the two special chemical effects. They suggest that the first effect could have been caused by the volcano reaction (further probing elicits bicarbonate plus acid) or by adding dry ice pellets. They then suggest exposed electrical wires or sodium metal could have caused the second special effect. The distribution of scores under the “special effects” condition shows much more perceived learning because they are engaged in active learning and it connects insights about chemistry and moviemaking.

SUMMARY The criteria for choosing movie clips to use in the chemistry classroom are those with highest ratings for pedagogical utility by teachers or “how much chemistry did you learn?” from students plus the highest movie Wow! from either group. The criteria that are not useful for selecting movie clips include the movie’s release date, its MPAA rating, whether it is in black and white or color, and whether it uses shocking language although student maturity should always be considered when making any choices for the classroom.



ASSOCIATED CONTENT

S Supporting Information *

A full list of the movies and ratings. This material is available via the Internet at http://pubs.acs.org.



AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. Notes

The authors declare no competing financial interest.





ACKNOWLEDGMENTS We gratefully acknowledge funding from the UNL Kelly Fund. The abstract graphic was created at www.wordle.com using the data used to create Figure 1.

DISCUSSION The methods described in this paper can be used to test the utility of any anchoring event, including chemical demonstrations, songs, and movie clips. We found that movie clips have higher pedagogical utility when they feature famous actors, amazing sets, and special effects although there is a broad distribution to the relationship. In contrast, movie clip Wow!



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