Discovering Watson's Crick in High School Chemistry Mark Whitman William Henry Harrison High School, West Lafayette, IN The first two weeks of school present a unique blend of the good and the bad, which makes the beginning of school a time of considerable adjustment for both teachers and students. Though many students possess a vibrancy and an eagerness to learn that may well he missing by November, their attention spans have been adjusted overthe summer to expect a commercial hreak every seven minutes. In addition, late arrivals, transfers, and student schedule changes serve to undercut attempts by the teacher to achieve classroom continuity early in the school year. T o accommodate these inherent idiosyncrasies best and still to achieve academic progress, I have heeun each of the ~ a sthree t school vears hv assienine to mv first year chemist& students "The ~ o u h l e ~ ~ e lhi ix~" a m e i Watson.' a verv readable account of the events leadine to the discove;y of the structure of DNA by Watson and Francis Crick. During the first two weeks, I tentatively allocate half of each class period to discussion of "The Douhle Helix," but I let class interest dictate. Some days the entire hour is consumed by such discussion, while on other days ten minutes will suffice. Regardless of the time spent, dividing the hour hetween text material and "The Douhle Helix" guarantees a hreak in discussion. Thus, the students are not forced early in the year to concentrate on one topic for a full hour. In addition, allotting substantial time to "The Douhle Helix," allows me to establish an academic atmosphere and to reintroduce my students to the discipline of study, without covering so much "fundamental"material that late arrivals will be hopelessly lost only two weeks into the school year. However, the true value of the hook is in its content, not just in its ability to buffer the nuisances associated with heginnine a new term. Watson's narrative is ilGmiuaiing and direct, and students rapidly develop a feel for the human side of science. Reading about Watson, Crick, Pauling, and the others who figure into the account, students come to r e a l i i that chemical knowledge is a product of real people with real feelings and real hang-ups as the hook removes the shroud of mysticism that the uninitiated sometimes associate with genius. One quickly comes to appreciate the role of the individual and the relations hetwe& individuals in striving for scien~ificachievement. The r e a d i n assimments coincide with start-of-the-vear lectures intended todevelop an understanding of the scientific method, and the lectures and reading complement one another well. Students find it exciting to follow Watson and Crick as they collect background information, develop hypotheses, test the hypotheses, and formulate new hypotheses. Mapping their progress awakens the students to the fact that scientific achievements are the cumulative results of the contributions and errors of a large number of individuals. T o view the blunders. as well as the achievements.. is ~articularlv . enlightening. I refer to the hook re~eatedlvdurine the remainder of the school year. 1f studentsire to understand the flow of Watson and Crick's investieations. i t is necessarv to discuss X-rav diffraction, hydrogen bonding, crystallog;aphy, macrom01~cnles, molecular geometry, and acids and bases. Obviously, during the first two weeks of the school year only the most superficial explanations can he made, but when we broach 'Watson, James 6.. "The Double Helix," New American Library. New York. 236
Journal of Chemical Education
these topics later, I see the lights come on when reference is made to our earlier discussions of "The Douhle Helix!' I have found it necessaw to conclude our study of "The Douhle Helix" with a short quiz, in order to present just rewards to those who have pursued the hook in earnest, as well as to those who have fallen along the way. I have real misgivings about quizzing my students over factual material from the hook. for i t is not the facts which make it valuable: however, some students will not invest their time unless they perceive a material benefit for doing so. This is the nature of the beast, and I am certain that the threat of the quiz encouraees a number of students to read the hook who otherwise woul~not. Two or three davs . ~. r i otor the ouiz the students are eiven a list of main characters and a set of questions that are t o he asked about the one s~ecificcharacter on the auiz. The identity of the character remains secret, until the name is pulled from a hat just before the students begin the quiz. The quiz is open hook, and while the students may not mark in the books, thev . mav . use blank bookmarks. The questions asked ahout'the character are place of employment, one area of scientificexpertise, one major scientificachievement, one distinctive personality trait, one error made which hurt hisiher chances for discovering the structure of DNA, and 6) the character's reaction to Watson and Crick's success. In addition to an answer. the students are asked to cite the pages in the teat from which their answers a)me. The inclusion of the citation insures that the students must become familiar with the hook, rather than rely upon their recall of class discussions; and to prepare answers for each of the main characters, the students must understand the hook's content. Each year, as I have read and reread the hook and have developed background material, "The Douhle Helix" has become an increasingly important part of my curriculum. For background information, I recommend volumes 159 and 160 of Science, which contain original reviews, as well as comments of some of the principal characters discussed in the hook. Below are some of my student objectives and some sample discussion questions. After reading "The Douhle Helix" students should: 1) 2) 3) 4) 5)
1) know the stem of the scientific method of research and how the" are utilized in the hook, 2) he aware of the individual differences among scientists,and how their approaches to the same problem may differ, and 3) be aware of the strong influence personalities and polities have
on scientific achievement. Sample questions include: 1) Chapters 1-3. What role do personalities and politics play in science? Be ahle to support your answer with examples from the
book.
2) Chapters 4-6. What is the difference between inductive and
deductive reasoning? Consult a dictionary. 3) Chapters 22-25. What was most surprising about Pauling's error? What were Watson and Crick ahle to determine from
Franklin's work that Franklin did not know? How would you characterize Watson's thinking at this point? Organized? Productive? What was Watson's new hypothesis?
