"Why do we have to know this stuff?" - Journal of Chemical Education

Making chemistry relevant for students; list of enrichment activities and take-home labs for each unit of a high school chemistry course...
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FRANK CARDULLA Niles Townshlp High School 9800 Lawler Skokle, lL60077

"Why do we have to know this stuff?" Lois Fruen Breck School, 123Ottawa Avenue North, Minneapolis, M N 55422 "Why do we have to know this stuff?" Do your chemistry students ask this question? Mine did, and perhaps many of our students harbor this thought, whether or not they express it openly. Because of this, I became convinced that significant changes were overdue in the courses I had been teaching and have thus greatly modified the content and character of these courses in a n effort to convince students that chemistry is meaningful. Breck School is a colleee-ore~aratow.co-ed dav school that prides itself on its ac;dkmi'c and racial diver;ty. SAT scores ranee from 280 ti, 700 on verbal and 320 to 800 on math. sin& almost 100% of the students take chemistry, the curriculum has to meet the needs of a wide range of students. What did I do to change the curriculum? First, I stopped using traditional published texts and put together two texts, one for the honors course and one for my regular chemistry class. In order to include new material in the regular course, I cut equilibrium chemistry from the curriculum. Because the students in the honors course can handle a faster pace, I left most traditional content in that course. Students Learn Relevant Chemistry In re-designing the chemistry curriculum, the second change I instituted was to make the subject contextually significant to my students. Chemistry is very relevant to the world in which they live. It was my job to show them just bow relevant, so I included material on the chemistw bf benzoyl peroxide ( I ) , the contents of their hair conditioners and make-up . (2).the chemistry of memory metals that regulate the temperature of their showers (3j, the chemistry of love (41, the chemistry of aerobic versus anaerobic exercises (51, etc. I decided t h a t no topic would be taupht without some practical aspect being discussed. Even quantum theory can be made meaningful when fluorescence, phosphorescence, whiter t h a n white clothes, Ultrabright toothpaste, and pigment color (6) are explained. Thirdly, to illustrate that chemistry is part of everyday life, I require students to earn a certain number of points for take-home experiments and activities. Since : many more experiments ~

and activities are available than they need to earn the points, students are able to choose those they most want to do. Not all students do all activities. They are able to choose from many different suggested experiments and activities; a list of these is given in the Appendix. P a r e n t s sign a form agreeing to r e q u i r e their s o n o r daughter to w e a r safety goggles w h e n doing take-home experiments, t o supervise t h e activity, and not t o allow t h e u s e of flammable substances for a n v take-home experiment. In wmi, expwimi!nt;i student: are asked to hcat mixtures to hieh tcmoeratures. Ifthe oarent feel.; the student is not matuye enoGgh to handle those experiments, the student is not permitted to do them. Sample TakeHome Experiments .Testing Physical and Chemical Changes with Household Chemicals (7) Making a Coiloid in Your Kitchen (8) Making a Suversaturated Solution (9) ~ a k i n an g ~kulsion(10) Finding Polar and Nonpolar Substances in Your House Rates of Reaction Using Alka Seltzer Tablets Making Hot and Cold Packs (11) Experimenting with Seotchgard (12) Finding the Weight of Your Car Using Air Pressure, Removing Tarnish by Redox (13) Making Silly Putty (14)

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Several of the take-home experiments, such as Making a Biochemical Polymer, have been taken from the Betty Crocker Cookbook. When writine the ~mceduresection for the students, I converted the kokbook taffy recipe into metric units. Students must convert the units back to cups

Lois Fwen holds a BA in chemistly from St. Olaf College and an MS from the College of St. Thomas. She has taught AP Chemistry, honors chemistry and regulai chemistry at Breck School for 17 years. She is a 1984 Dreyfus Master Teacher. In 1986she received the Presidential Award for Excellence in Science Teaching. In 1990 she received the National Science Teachers Association Distinguished Teaching Award and the Chemical Manufacturers Regional Catalyst Award. In 1992 she received the James Bryant Conant Award from the American Chemical Society and a Tapestry grant from the Toyota Corporation and the National ScienceTeachersAssociation.She has received grants from the American Chemical Society, Eisenhower Funds, Cray Research and the Minnesota High Tech Council. The Minnesota Environmental Science Foundation, Inc., and National Science Foundation to forward her ideas in education.

Volume 69 Number 9 September 1992

737

Topic 1. Hazardous Elements in Your

Home 2. Additives in Your Food 3. Nuclear Power 4. Radon Gas in Your Home 5. Greenhouse Etfect 6. Disappearing Ozone 7. Recycling Aluminum. Glass, Paper, etc. 8. Acid Rain in Minnesota 9. Drugs 10. Protecting Your Environment 11. Disappearing Hydrocarbons 12. Chemical Warfare

Unit for Use with Topic

introduction of Elements Naming of Compounds Radioactive Isotopes Radioactive Isotopes Gas Laws Intermolecular Bonding Intermolecular Bonding Acids and Bases Acids and Bases Solutions Organic Organic

and teaspoons in order to do the experiment in their kitchens. Parents Encourage the Take-Home Asslgnments Some parents have commented that their sons and daughters have destroyed the kitchen (in one case by permanently fixing a sheet of wax paper to the countertop). But, in the three years I have been requiring take-home lab work, every one of the parents, whose kitchens will never be the same again, have strongly encouraged me to continue this part of the course. Combined Learning Opportunities Join Forces Chemistry, English, Information Retrieval, and Societal Issues

Finally, because students are interested in more serious topics that affect the world in general, and because students need to learn good writing and information retrieval skills in science as well as in English classes, 12 societal issues are included in the chemistry courses. Chemistry stndents a t Breck were surveyed on areas of science that most interested them, and 12 soeietal issues were chosen based on their interests. These topics are introduced when most appropriate. For example, methods of recycling aluminum, newspapers, glass, and plastic are researched when students study liquids and solids; and caffeine, cocaine, aspirin, PCP's, and nicotine are studied during the acid-base unit. The 12 societal issues are listed in the table. Students work in cooperative learning groups to research a topic of their choice on each societal issue. For example, when studying hazardous elements in their homes, students might choose to research the dangers of lead in soldered plumbing lead-lined drinking fountains pottery glazes lead-based paints mercury in dental fdlings copper cookware cadmium in artists paints aluminum in soda cans Students identify and locate information on their topic using print, microfiche, newspapers, videotapes, and computer formats. Students use HyperCard to write on the societal issues. Hypercard is a Macintosh computer program that organizes information, allowing stndents to combine words, 738

Journal of Chemical Education

formulas, pictures, and sounds in an infinite variety of ways. Rather than typing a research paper on the societal issue, students use their creativity with Hypercard. Stndents are expected to incorporate text, chemical formulas and information, and pictures and graphs, as well as to use correct grammar and spelling, and to employ appropriate oarenthetical documentation and bibliomanhical formats. h e writing center teacher works with the &dents on correct use uf oarenthetical and bibliomaohxal formats. Students peer Ldit other stndents'pro&a&s to learn about the different asoects of each societal issue as well as to improve their writing and presentation skills. Since inntitutine these chanres. 1 have observed that far fewer students the relevance of what they are being asked to learn. Students Are Interested in InterestingChemistry It is interesting that the students in my regular courses, especially the girls, seem very interested in pursuing careers in science. They seem to be more interested and more motivated than the students in the honors course or students from traditional courses I have taught in the past. They are the students who apply for summer research programs, who attend chemistry and physics events a t local colleges, and who participate in the chemistry shows that we hold for elementary and middle school stndents. Unfortunately, these young women are also the students who return to Breck saving that they do not wish to take more chemistry after i h e s freshman college experience. They say there are no demonstrations, no interesting labs that fit the material being covered in class, no practical examples, and no material of as much interest as their other subjects. Chemistry Teaching Methods Make a Difference Chemistry is not less interesting than other subjects. I think that it is just being taught in an uninteresting way Arecent article in NSTA Reports! says that science faculty often contribute to the attrition rate for chemistry majors by structuring their courses so only the best will remain. The article quoted a professor on this weeding mentality:

We're not just weeding the people out, we're ripping out half the garden (15).

I think that what is missing from most high school and general college chemistry syllabi is the practical, interesting chemistry. There are those who will say they do not have time for the practical stuff. I say, "Make time". There are others who are more used to weeding stndents out of chemistry than making it accessible to students who are not traditionally attracted to chemistry. I say, let's make this material accessible to nontraditional chemistry students. There are also administrators and school boards to contend with, such as the administrator who accused a friend of mine, who uses my text, of teaching "peanut brittle" chemistry. Her stndents were having too much fun in chemistry class, so, in her principal's mind, she wuld not have been teaching rigorous chemistry. Just because published texts, achievement tests, and general college chemistry syllabi suggest that we must cover a given amount of chemistry in a standard way, does not mean that they are right. If more ofus decided to make chemistry more meaningful, more immediately relevant, more accessible, and more fun, the textbook, achievement test writers, and general college professors, might just see the validity of this philosophy. Let's All Teach Chemlstry that Captivates The next time you hear the question," Why do we have to know this?", stop. Make a change. It takes time to apply