From San Juan to Madison: Cultural Perspectives on Teaching

From San Juan to Madison: Cultural Perspectives on Teaching General Chemistry. Mary Ann Davison Fernandez. Departamento de Química y Fisica, ...
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Chemistry Everyday for Everyone

From San Juan to Madison: Cultural Perspectives on Teaching General Chemistry Catherine Hurt Middlecamp* Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706 Mary Ann Davison Fernandez Departamento de Química y Física, Universidad Interamericana de Puerto Rico, San Juan, PR 00919-1293

This article is for instructors of Hispanic students and for those interested in increasing their repertoire of culturally relevant examples for teaching. It is based on the collaborative experiences of the authors, one of whom lives in the Midwest and the other in the Caribbean. As we jointly prepared materials for general chemistry, we noted that (i) chemistry instructors on the mainland tend to have minimal knowledge of day-to-day life in Puerto Rico and could benefit by knowing more;1 (ii) real-world examples drawn from a variety of cultural settings can be helpful to all students; (iii) Puerto Rican students have difficulties with English to which instructors should attend; and (iv) these difficulties are illustrative of those experienced by all students for whom English is a second language. To aid the reader, a brief review of Hispanics in higher education is first presented. Next, we point out chemical concepts that have different applications in Wisconsin and Puerto Rico. Examples of chemical concepts set in other Hispanic cultures are then described. To conclude, we turn to language difficulties, offering both suggestions and resources for those who teach Hispanic students. Although the specifics may vary, the content described here is applicable to other groups of students as well. Hispanics in Higher Education There is no such thing as the Hispanic student, just as there is no typical Asian or Caucasian student. The term Hispanic encompasses many diverse Spanish-speaking groups (1, 2). A person from Puerto Rico is likely to be Hispanic, but other adjectives apply as well: first a female student would be puertorriqueña (i.e., from Puerto Rico), next antillana (i.e., from the Antilles), then caribeña (i.e., from the Caribbean), and finally hispana. The descriptions latino and chicano encompass an even broader category of Spanish-speaking peoples. These terms have taken on various meanings over time, and most instructors find that individual students prefer, sometimes strongly, to describe themselves using one term rather than another. When statistics for the category Hispanic are reported for U.S. higher education, the meaning is not always clear. For example, some counts include the number of islander Puerto Ricans, whereas others include only those from the fifty states. Some counts include individuals who speak no Spanish, but have Hispanic family members; others do not. Finally, some totals include estimates for individuals who, *Email: [email protected].

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because of their immigration status, may not be counted by the usual means. According to a 1996 survey from the American Council on Education, there are more than a million Hispanic students enrolled in higher education in the fifty states (3). This represents a greater than 35% increase in the number of Hispanics since 1990. Roughly a third of these students study in California, followed by Texas, New York, and Florida. Hispanic students earned a total of 882 doctorates (all fields) in 1994, an increase of 6.3% from the previous year. In 1992, 108 doctoral degrees were awarded to students in the physical sciences, of whom 26 were Puerto Rican. An author comments: “Of the Ph.D. degrees granted to Puerto Ricans, I estimate that 90% were granted to students who received their bachelors degree on the island of Puerto Rico. In fact, the University of Puerto Rico, Mayagüez campus, produced 40% of all bachelors degrees granted to U.S. Hispanics in science and engineering in 1990” (4). Even with this progress across all levels of higher education, Hispanic men and women continue to be underrepresented. Relative to their Asian and Caucasian peers, they do not achieve as many positions in higher education and professional fields. Hispanic students are likely to have few role models, and their instructors may be unaware of their cultural needs. Although these facts alone provide motivation for instructors to be more knowledgeable of Hispanic culture, increased knowledge has the potential to benefit all our students, as the following sections illustrate. Chemistry in Cultural Contexts Daily life experiences in Wisconsin and Puerto Rico contrast sharply. Chemistry instructors in both locales can utilize these differences to provide a wider range of teaching examples. The benefits of teaching with examples drawn from different cultural settings are twofold: this practice recognizes and includes the life experiences of students from those cultural settings, and it offers all students examples that put chemical principles in the largest possible context. For example, we were both involved in a dinner-table conversation concerning a project to study radon levels across the state of Nebraska. The question arose, “Is radon a problem in Puerto Rico?” We had no ready answer. Initially, we discussed whether radon could be produced by the island’s subsoil and rocks. We knew the island was of volcanic origin. Although volcanic rocks presumably could produce radon, none of us was aware of any buildings in Puerto Rico being tested for it. After some discussion, our

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line of reasoning shifted. The key issue did not seem to be whether radon was present, but rather if its presence mattered. Radon is problematic in living spaces such as basements or tightly weather-stripped rooms where it can accumulate. Neither of these is the norm on a tropical island. In Puerto Rico, most homes rest on concrete slabs and utilize louvered windows to maximize the ocean breezes. Even if radon were seeping upwards from the island subsoils, its accumulation in living spaces would be unlikely. Later, we sought additional expertise. A geologist informed us that radon formation would be likely in the silica-rich volcanic rocks (rhyolite) of the island. However, by asking

Example 1. Team question from laboratory experiment on radon Form a team of three people. Each of you should work on one of the following questions. Then compare your answers, noting any assumptions that you have made. (a) Consider a beach-side home in Mayagüez, Puerto Rico, a university town on the west coast of this volcanic Caribbean island. The home is built on a concrete slab and has screen windows. Is radon likely to be a problem for a home-owner in Mayagüez? Why or why not? (b) Consider a two-story office building in chilly Duluth, Minnesota. The building is well insulated and sealed against the winter arctic blasts. Is radon likely to be a problem for the occupants of this building? Why or why not? (c) Consider a two-story farmhouse in rural Nebraska. The basement has a dirt floor with underlying limestone rock. Is radon likely to be a problem for the farmers who have lived there for generations? Why or why not?

Example 2. Sample challenge questions for small group discussion† 1. Dimensional Analysis and Estimates: Build a Better Tortilla Provide article from Science describing the Tortilla Project (10), as well as a tortilla wrapper. (a) What ingredients are in a tortilla? Use the information provided on the wrapper to determine the mass of a tortilla in grams. If the tortilla were an inch greater in radius, how would the mass change? (b) The authors state that more than 10 million tons of corn tortillas are consumed in Mexico each year. This is an estimate. To obtain this figure, what assumptions might the authors have made? Suggest two mathematical routes to coming up with the number 10 million. (c) If 800 million tortillas are produced each day in Mexico, roughly how many are produced per person? Given this information and the fact that 10 million tons are produced a year, how many grams does each tortilla weigh? How does this compare with your answer from part (a)?

2. In Puerto Rico, your glasses may fog up when you exit an airconditioned building. In Wisconsin, your glasses may fog when you enter a heated building. Explain the differences. (Can you think of any other scenarios involving windows, such as car windows?) –––––––––––––––––– † These questions are presented in a format suitable for small group discussions. With slight modification, they also may be used for discussion in lecture, as assigned homework problems, or as take-home exam questions.

about Puerto Rico we learned more than just a new geological fact. By switching the cultural context of a question, we came to more fully understand the issues involved in assessing the risks of radon. Our conversation was an example of “constructing knowledge” (5). As we sought an answer, we analyzed the situation using our prior knowledge and experiences. From these, we actively built new questions and areas of inquiry. The discussion progressed because each of us could contribute different scientific and cultural information. The connection of our discussion to good pedagogy was clear. Just as we had benefitted from exploring the issues, so could our students. Example 1 shows how such a question now is utilized by one of us in a collaborative learning situation (6 ). With discussion, we generated additional examples that teachers could put to use.

Condensation: Foggy Glasses and Windows On a winter day in Wisconsin, if a person wearing glasses steps inside, his or her glasses usually fog up. In Puerto Rico the reverse is true. Upon exiting an air-conditioned building and stepping into the humid tropical air, one’s glasses fog. Similarly, people in Wisconsin experience winter ice buildup on the inside of their cars and on windows at home. In Puerto Rico, condensation occurs on the outside of their car windows or windows at home. Example 2, part 2, presents this information in the format suitable for group discussion. Rusting and Its Cause Wisconsin has few rust-free cars. The culprit is the rock salt spread on the sidewalks and roadways. In the capital city of Madison, roughly a million pounds of salt are thrown on the streets each year. This salt quickly finds its way to the underside of cars and provides an electrolyte to facilitate the rusting process. Puerto Rican cars can be rusty as well. Obviously Puerto Ricans do not salt their roadways; coastal salt spray (“el salitre”) is the source. In Wisconsin winters, you take your car to a car wash after driving on the salted highways. In Puerto Rican summers, you hose down your car after driving to the beach. Water Treatment When teaching topics like water softening and desalinization, it may be helpful to point out to whom they are relevant. Few people have water softeners in Puerto Rico. However, insuring a supply of fresh water is of concern, especially in the San Juan area. In Wisconsin, many people utilize water softeners. However, a supply of fresh water is not a problem. Ozone Although Americans may worry about UV radiation and the ozone hole, the issue is perceived differently in Puerto Rico. In Puerto Rico, the sun always feels “hot” and its intensity does not vary to the extent that it does outside the tropics. Thus, many Puerto Ricans use protection from the sun all year round. In contrast, people in the higher latitudes use sun screen periodically, as they are concerned seasonally about excessive solar radiation. In actuality, there is reason for global concern in all latitudes, even though people may behave differently.

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Chemistry Everyday for Everyone

A Broader Context The examples just cited can be viewed in broader terms. Rather than just representing the Midwest and Puerto Rico, they could serve to contrast any tropical region with a northern climate. Such examples can be difficult to find. To provide a greater selection, a multicultural project for high school and college chemistry courses was recently initiated (7). In addition, there are several general publications on science across cultures for secondary school teachers (8, 9). Finally, topics such as the chemistry of art or of wine-making are inherently crosscultural and have been reported regularly in this Journal. While the literature of specific teaching examples is still sparse, it can be expected to grow as we acknowledge the needs of increasingly diverse students. Puerto Rico is but one of the geographic regions of Hispanic culture to which we can turn for examples. In the United States, Hispanic groups include those from Mexico (the largest), Cuba, and Central America. Mexico recently has offered several examples of chemical principles in action. In 1995, Science reported on the “Tortilla Project”, launched by a group of physicists, biochemists, cereal chemists, and mechanical engineers (10) to improve upon the process by which tortillas were made. Why a new tortilla? “The tortilla”, reports Jesús González Hernández, the team leader and a physicist, is a “water-guzzling, energy-sapping, polluting beast”. The project was initiated with the hope of using less water to soak and wash the corn, using less energy to cook the raw product, and creating a more nutritious product. The Tortilla Project provides a wealth of information on which chemistry students can try out their problem-solving skills. More than 10 million tons of corn tortillas are consumed in Mexico each year. Ten thousand liters of water are used to soak and wash the corn for each ton of tortilla. The discarded waste water contains high concentrations of slaked lime, calcium hydroxide, which is used in the manufacturing process. The cooking process is performed largely with individual gas-fired burners in small shops and is both polluting and wasteful of energy. These facts can be used to generate questions that range from straightforward manipulations to more challenging problems that require a group effort (Example 2). Other issues raised by the researchers can be explored as well. For example, what is infrared light? How would the efficiency of the cooking process be different if infrared light were used as a heat source? What is calcium hydroxide? What role does it play in the manufacturing process? Science also recently ran an article on the urban smog in Mexico City (11), a devastation to which any traveler or resident will attest. Automobile and industrial emissions are known contributors to the smog. The researchers identified liquefied petroleum gas (LPG), a fuel used for heating water and for cooking, as a culprit as well. In a first-year chemistry course, the chemistry of gasoline is more likely to be taught than that of LPG. LPG, however, is a fuel of global importance. Students could research its composition. How is it produced and how does it differ from gasoline? Both industrial and photochemical smog can be used to illustrate chemical principles. What is the chemical composition of the smog? How might one determine whether the smog originated from automobile exhaust, industrial emissions, LPG, or a combination of all three? How much LPG is consumed in cooking 100 tortillas and what are the emission products? 390

In presenting these examples, we hope readers recognize that the intent is not to start teaching all Puerto Rican students about the science of tropical islands nor Mexican-American students about tortilla chemistry. Clearly, this makes as little sense as having Wisconsin students focus solely on the chemistry of milk (or beer). Rather, there is a twofold message for instructors: (i) teaching examples should be tailored to the students you teach, inclusive of their lives and heritage; but at the same time, (ii) examples should be drawn from a variety of geographic regions and cultures, better both to explain how chemical principles apply and to prepare students for the global marketplace that they will enter upon graduation. Hispanic Students in the Chemistry Classroom Programs that offer academic support to Hispanic students have been reported in this and other journals (12, 13 ). Professional organizations such as the Society for the Advancement of Chicanos and Native Americans in Science (SACNAS) exist to provide support. Issues relating possible learning styles, the influence of the home environment, and the cultural influence of language for Hispanic students have been reported in the literature. See, for example, the work of Rakow and Bermudez and the references therein (14). Two excellent, more general position papers on Hispanic women in higher education were recently published (1, 2), the latter containing a section on black Hispanics. More generally speaking, excellent books exist to help the science instructor with language minority students (15, 16 ), and a recent journal issue devoted to teaching ESL students cites many useful references (17). It is important, however, to know the trouble spots for a particular language in one’s own discipline. Hispanic students range from those with total mastery of the English language to relative novices. Of concern here are those with more limited English proficiency. Here are four examples of language difficulties, specific to learning chemistry in English/Spanish. 1. Chemical concepts may be difficult to translate. Native English speakers are unlikely to consult dictionaries as they read chemistry textbooks or lab manuals. Students whose English proficiency is lower, however, consult dictionaries frequently. For example, consider the words buffer and yield. Buffer translates as “pulidor”, a polishing cloth, or as “amortiguador”, a shock absorber in a vehicle. Pocket dictionaries do not provide chemical meanings, unless the student happens to have one of the scientific dictionaries that are just beginning to become available. The term yield presents a different problem (“ceder” is to yield; “rendimiento” is yield). Students see YIELD on road signs and learn that this means slow down, look, and yield if necessary. They may not readily relate yield to how much of a product is formed. Other terms, such as graduated cylinder and titration may not even be in a dictionary, and lab manuals typically provide no glossaries. 2. Words may not have an equivalent (or may have additional) meanings. In English, heat and temperature are two distinct concepts, albeit ones often confused. In Spanish, however, the word “calor” is used for both heat and hot (“calor de reacción” = heat of reaction; “Hace calor” = It’s hot). Thus, in Spanish a student could be told to measure “the heat” with a thermometer (“Mide cuanto es el calor afuera con el termómetro”)

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Chemistry Everyday for Everyone and may not realize that two different words exist in English. A laboratory manual may direct a student to test a solution for some property. When the verb test is translated, it is either as the verb “probar” (as in try or taste) or “examinar” (as in to take an exam). These translations are problematic, the one to taste being potentially dangerous. The command form in Spanish, “pruebalo”, could also mean to taste it instead of to test it. 3. Cognates may not directly translate. Words from different languages that are similar do not always have the same meaning. For example, the Spanish word for crystal is “el cristal”. This also can refer to the material of glass. The problem arises in that “el cristal” (crystal) is not “amorfo” (amorphous), but “el cristal” (glass) is. Similarly, the word spectrum can be confusing, because in Spanish “el espectro” can mean a ghost. 4. Mnemonic devices may not translate. Mnemonic devices that are helpful for English-speaking students may not aid those whose native language is Spanish. For example, ROY G. BIV does not translate. The color indigo is not normally used in Spanish. Colors are often indicated in connection with fruits, such as “verde aguacate” (avocado green) or “verde limon” (lime green).

Suggested Practices and Conclusion Most of the examples in this article have been cast in terms of Puerto Rican students studying chemistry on the mainland. However, the principles involved should generalize easily to teaching chemistry in any situation where one culture predominates, yet members from other cultural groups are present. In summary, we encourage the following. Include examples of chemical concepts that are familiar and meaningful to those in cultural settings other than your own. This not only should help the learning process for students who come from other settings, but also should improve the understanding of chemical concepts for all students. Increase your awareness of language difficulties. Some languages, such as English and Spanish, map reasonably well onto each other. However, as pointed out earlier, there still are important differences. Languages even more distant from English present particular challenges. For example, a southeast Asian student reported that he had no word for “pressure” in his language, but noted many more words for the colors of the spectrum. Let your students be your teachers. We both continue to be amazed by the wealth of useful examples and information that our students bring to us from their own life experiences. They may well be able to articulate them, given a listening ear. Finally, we urge colleagues to reinvent neither the wheel nor the flat tire. You may be able to glean wisdom from colleagues who have taught abroad (18). Leaders in your own community may have assembled cultural materials appropriate for instructors. Professional organizations such as the American Chemical Society, American Association for the Advancement of Science (e.g., Proyecto Futuro), and National Science Teachers Association have addressed the concerns of Hispanic

as well as other groups of students. It is our hope that by being more inclusive of a variety of cultures and the daily experiences they offer, all students will benefit. Acknowledgments We would like to thank Mercile Lee and other members of the UW Inter-Institutional Linkage Program who made our collaboration possible. In addition, we would like to thank Ingrid Montes of the Universidad de Puerto Rico, Rio Piedras campus, who also participated in the Linkage Program; Judith Rosenthal of Kean College for her expertise about teaching students for whom English is a second language; John Valley of the UW Geology Department for his information on radon; Tony Jacob, Roberto Ibarra, and Betty Moore for their help at various points along the way; and the former Nebraskans Betsy Kean and Marion O’Leary, for their dinner conversation about radon. Note 1. Although presumably the reverse is true for instructors in Puerto Rico, this did not seem to be as pressing an issue. Those on the island generally used instructional materials produced in the United States and tended to be bilingual.

Literature Cited 1. Ibarra, R. Enhancing the Minority Presence in Graduate Education VII: Latino Experiences in Graduate Education: Implications for Change; Council of Graduate Schools: Washington DC, 1996. 2 . Nieves-Squires, S. Hispanic Women: Making Their Presence on Campus Less Tenuous; Association of American Colleges & Universities: Washington, DC, 1991. 3. Carter, D. J.; Wilson, R. Minorities in Higher Education; American Council on Education: Washington, DC, 1996. 4. Castro, G. In Diversity in the Chemical Workforce of the 21st Century; American Chemical Society: Washington, DC, 1994. 5. Bodner, G. J. Chem. Educ. 1986, 63, 873. 6. Laboratory Experiments for Chemistry 108, Fall 1997; HaydenMcNeil: Westland, MI, 1997. 7. Hayes, J.; Perez, P. Integration of Multicultural Content into Introductory/General Chemistry Courses; Presented at the 14th Biennial Conference on Chemical Education, Clemson University, August 4–8, 1996; Brackett 220, Paper 6; abstract, p 10 (program). 8. Science for All Cultures; National Science Teachers Association: Arlington, VA, 1993. 9. Multiculturalism in Mathematics, Science, and Technology: Readings and Activities; Addison-Wesley: Menlo Park, CA, 1993. 10. Cohen, J. Science 1995, 267, 824. 11. Blake, D. R.; Rowland, F. S. Science 1995, 269, 953. 12. Gomez, F. J. Chem. Educ. 1990, 67, 318. 13. Rakow, S. J.; Bermudez, A. B. J. Coll. Sci. Teach. 1988, 17, 353. 14. Rakow, S. J.; Bermudez, A. B. Sci. Educ. 1993, 77, 669. 15. Rosenthal, J. Teaching Science to Language Minority Students; Multilingual Matters: Bristol, PA, 1996. 16. Scarcella, R. Teaching Language Minority Students in the Multicultural Classroom; Prentice-Hall: Englewood Cliffs, NJ, 1990. 17. Approaches to Teaching Non-Native English Speakers Across the Curriculum; Sigsbee, D. L.; Speck, B. W.; Maylath, B., Eds.; New Directions for Teaching and Learning 1997, 70. 18. George, P. G. College Teaching Abroad; Allyn and Bacon: Boston, 1995.

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