One day about eight years ago, Cabot Professor of the Natural Sciences John E. Dowling and Baird Professor of Science Dudley R. Herschbach invited a colleague out to lunch.
"[They] said they had this project they'd been involved in for some time-to reform curriculum for people in life sciences, especially pre-med," recalls Menzel Professor of Astrophysics David Layzer.
"We wanted to have a better sequence of courses leading up to biology courses that would actually use chemistry and physics," he says. "I'd been teaching large core classes which met in small discussion sections, and they asked me if I'd be interested in forming this new introductory course."
What Layzer created is one of the most innovative courses at Harvard. As an alternative to Chemistry 10, Layzer and Professor of Chemistry Cynthia M. Friend now offer the year-long sequence Chemistry 8 and Chemistry 9.
The course, which is open to students who place into Chem 10 and Math 21a, combines physics, chemistry and math in a small group setting rarely found in other science classes.
Most students in the class are also concurrently enrolled in a small section of Math 21 tailored especially for the course. When taken with these math sections, Chem 8 and 9 fulfill the physics, math and general chemistry requirements for pre-med students.
The course is unique among Creating the course has forced Layzer and Friend to devise a new method for teaching chemistry and physics. When Layzer began work eight years ago, one of his first steps was to replace the typical science textbooks used in introductory chemistry and physics courses. "Introductory chemistry and physics books can't possibly be read--they're more like reference books," he says. "I set out to write not a textbook, but a narrative, with a lot of examples and a real story. It would have a plot and a beginning and end, and be in the language of science and math." Layzer also says that while the narrative covers chemistry and physics, it is intended to teach the subject matter as it is relevant to life science majors. He says, "I began with molecular biology textbooks and worked backwards, thinking. "What would you need to know to understand this?" The result of this work is a class which, while extremely challenging, is very popular with the students who take it. It is a dynamic course, where Layzer and Friend frequently experiment with the teaching approach. In the course's first year, it was "much, much too hard," Layzer says. "The course has gotten more pleasant to take, but not watered down. The material has been better adapted to the way a human mind works." In its unique approach and small, intimate class size, Chem 8 and 9 may hold important lessons for instructors in other science courses, particularly introductory ones. "This class is very intensive in terms of teaching staff--we need a lot of instructors," Friend says. "It is interesting to think how the subject material and approach to teaching could be used for a larger group of students." Integrated Approach Chem 8 and Chem 9 give students the same credit as two more common introductory courses, Chem 10 and Physics 15a. But undergraduates and instructors in Chem 8 and 9 say their class presents chemistry and physics in an integrated way. "The principle behind Chem 8 and 9 is that we wanted to integrate introductory physics and chemistry, since there's a lot of overlap," Friend says. "There really is not a line between chemistry and physics--there's more of a general approach." Layzer and Friend say the class is still a work in progress. They would like to see the two semesters of the course become more integrated and less difficult. Indeed, students intrigued by the prospect of a science class without finals should be warned that Chem 8 and 9 is far from easy. Students who have taken the course rountinely call it one of the hardest classes they have encountered at Harvard. "We do the mathematics very rigorously," Friend acknowledges. The problem sets on which students' grades are based are notoriously difficult. That may be because of their focus on explaining concepts rather than "plug-and-chug" problem solving. "The professor will leave one part of a concept unexplained, and ask you in a problem set to draw a conclusion," says Cedar Reiner '98. "He will leave blank gaps in logic for you to fill in." David Jan '97, who took the class during his first year, says instructors sought to increase students' understanding, not to spoon-feed answers to them. "The emphasis wasn't on getting drilled and doing problems," Jan says. "We would do essay-type answers even in math." This rigorous approach is what makes the course so challenging. "It's really difficult to do that sort of thing--you know that if you can explain some-thing then you really know it." Elisends Grigsby '98 says. "It takes time just to adjust to that." Students says the course's size and format has helped them adapt to the difficulty of the work. Those who have taken the class say it gave them an understanding they might not have developed in larger introductory classes. "Our TF always says that we pay for not having exams," Grigsby says. "When I think about homework I think about doing math or Chem." Questions and Answers The course meets in Boylston Hall, in a spacious corner classroom with arching windows. Students sit in a circle and discuss the material of the previous session; occasionally one of them will come to the board to demonstrate a concept. When students have a question, it can be addressed either by the professor or by their peers. The instructors say this discussion format helps students to learn from each other and to ensure that they are receiving the teaching assistance they need. After class is over, professors spend time with individual students if they have questions. "Chem 8 is a much smaller class than Chem 10," Friend says. "It's not lecture-based, and that allows for us to make sure the" questions students have are fully answered." Josh Greene '96, who also took the class during his first year, says the close contact with the professors was one of the best things about the course. "I generally though [the course] was very well-arranged," he says. "I enjoyed having an active role in the class and having the professor know my face and say 'hi' to me if he saw me in the Yard." Greene says he took the class to fulfill his Science A.core requirement. He says he ended up being especially impressed by the way the course was constructed. "We would have a problem set and then a revision," Greene says. "I think it was an effective system because it makes students go over what they've learned." "There's a passive style of learning which large lecture classes like Chem 10 allow, and an active style which Chem 8 and 9 demand," Greene adds. "You can't get by passively in a class as small as Chem 8 and 9." William Kaminsky '98 says one benefit of the class structure is that it makes students and teachers accountable. "You're not allowed to slip through the cracks--to hand in a problem set you don't understand and just move on," he says. Women in Class Friend and some students in the class say the small size and non-competitive atmosphere may be especially attractive to female science concentrators. About 25 percent of Chem 8 and 9 students are female. "One aspect is that women teel isolated in a large lecture class and it's hard for them to function," says Friend, who chaired the faculty standing committee on women for three years. "This might lead them to leave the sciences." "The environment in Chem 8 is oriented towards discussion, and the students get to know the faculty better," Friend adds. "It's much less likely that a student would feel on the margins of the class." Liz Pine '97, a former student and a current teaching assistant for Chem 8, says she enjoyed the inclusive feeling in the class. "It was completely non-competitive," she says. "I would work on problem sets with my classmates." Pine says, too, that the inclusiveness may make the course more attractive for women. "I think [the small, discussion format] is good for all students, especially females," she says. "I think guys get the short shrift in a large lecture class, too, but women may be harder hit." "Studies show that learning in groups is much better for female students than large lecture classes and learning by your-self," Pine says. Accessible Pine says another advantage of Chem 8 and 9's discussion approach is that it allows students to pick up the context and background of the material taught in the course. "I enjoyed knowing where the ideas were coming from and not just being told something," she says. Layzer says the course's format also makes it manageable for students with varying amounts of science and math experience. "The class was designed to be accessible to many different experience and ability levels," he says. "It will challenge those who have strong backgrounds and yet will be accessible to people with weaker backgrounds." Many students, however, feel that a certain amount of background--not to mention an extraordinary amount of motivation--is necessary to function in the class. "I had to do a lot of learning on my own, since my background in physics was very weak," David B. Jan '97 says. While he found it hard to catch up, Jan says the instructors were attentive to his needs. "People were accessible when I needed help," he says. "There were two teaching fellows and two professors for math, and two teaching assistants and pone professor for Chem." Now, with Friend's addition to the course, there are two professors for Chem 8 and 9. Jan recommends that a student have a strong background in physics and math before entering the class. A backgrounds in chemistry is also useful but to as lesser degree, he says. Perhaps the most important prerequisite for the class, however, is the motivation and willingness to discuss questions about the material, students say. "You have to learn to read a sourcebook and textbook and be willing to ask questions in class," says Melody Wu '98. The reward for student's hard work is a deep understanding of the subject mater, they say. Pine says many students who took Chem 9 in the spring managed to take organic chemistry (Chem 20) simultaneously without any problems. Others were enrolled in Physics 15b concurrently with Chem 9. Students leaving the course say they feel prepared for almost any other science class at the College. "The students learn more than just the material--they learn a way of thinking." Pine says. "They get an analytical system for how to look at a situation. It teaches you how to model things." Course's Future Layzer says he would like to see more students enroll in Chem 8. Undergraduates who were turned off by their physics classes in high school would be likely to enjoy the class in part because it teaches "the music of physics," he says. Too often in high school, physics is presented as difficult and inaccessible to most students, according to Layzer. Both Friend and Layzer say they have several ideas for the course's future. For example, they say they want to lighten the workload slightly. "We're trying to make the problems more do-able than they were before, both in quantity and quality," Layzer says. "Right now the workload is a little too heavy." Both professors say lessons learned in Chem 8 and 9 should be applied other science courses. They recognize, of course, that it may not possible to get every student into an introductory science course with only 15 students. "Introductory classes play a large service role since many students take them to fulfill concentration or grad school requirements." Friend says. "That's why it's hard to have a class like Chem 8, which functions ideally with about 15 students. "It's not the traditional approach."
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