Chapter 5: HeLa Cells, High-Speed Chases, and Other Essential Questions

Chapter 5. Helicels, high speed chases, and other essential questions. Because science class should not be a trivia game. The only sound in the biology classroom was the voice of one student as he began reading aloud. On 4 October 1951, a young black woman named Henrietta Lacks died of cervical cancer. An image of the book cover for the immortal life of Henrietta Lacks was projected on the front screen as he read. At the end of each paragraph, Grace called on a different student to continue. This was not a strategy she used often. After all, the students had been assigned the article to read for homework. But the hushed and respectful tone she set for the read aloud was necessary for the subsequent conversations she had planned. Some students tried to break into the reading with questions, but Grace held them at bay. Students heard that Helicels, which are commonly used in research because of their unique properties, were named after Henrietta Lacks, the patient from whom they were harvested without consent. Yet, another reader continued, "Henrietta's body lies in an unmarked grave, while her children have revealed they did not learn for more than 20 years that their mother's cells were still alive and had been used to create an entire branch of medical science." Grace asked the students to discuss at their tables whatever thoughts they had about what they had just heard. Once they had talked for a bit, she quieted the class and asked, "So how are you feeling about this?" The students' responses covered a wide range of topics from health insurance and the purpose of hospitals, toward it means to sign a form and give consent. One student commented that race had to be a factor in the story of Helicels, and another thought that it was unfair that the family received nothing from the research. So, Grace asked, setting the table with an essential question that would guide the next week of mytosis lessons, "Who do you think owns the rights to their cells?" Typically, essential questions are open-ended without a single definitive answer and require students to synthesize information across a range of sources and perspectives as they progress through a topic. A well-written essential question serves as a portal to the discipline in that being able to address the question represents mastery of the intended learning subject matter. The driving purpose of an essential question is to kindle a student's internal motivation for a topic by situating the subject matter to be learned within an authentic context, and effective essential questions are designed to ensure that student learning is propelled by important and recurring themes. When science teachers use essential questions to frame their units, they provide students with another pathway for learning science content. Sometimes, essential questions press for an explanation to a puzzling phenomenon, like, "Why does the moon seem to change its shape?" Others create openings for science to connect to a broad range of social issues and ask students to develop value judgments. The ethical and moral dilemmas we face as a society often emerged naturally in a science classroom within certain topics. Studying the atom may precipitate discussions about nuclear energy and weapons. A unit on genetics may lead to a dialogue about the ethics of stem cell research, or the use of genetically modified organisms in the food supply. A lesson on hurricanes and severe weather may serve as a stepping stone to a debate about segregated housing patterns and construction in flood-prone areas. Science education often makes space for discussion, debate, and dialogue about such issues, and while some are considered dispassionally at a distance, should humans colonize Mars, others are immediate and visceral. Why do so many students in our school have asthma? There are a number of different ways for essential questions to draw upon authentic problems to frame science learning. One is the notion that science class is an appropriate place to discuss and debate socio-scientific issues of importance. The socio-scientific issues are more than just discussions with opinions. They are arguments, informed by scientific reasoning and evidence. Their use in science classes can be seen as a way to enact sophisticated educational objectives of evaluation, and as a justification for learning particular content. For example, the socio-scientific issue of whether or not humans ought to tinker with the DNA of sex cells or an embryo, in order to produce a designer baby, provides a compelling rationale for students to learn about genetics and meiosis. Another use for essential questions is in problem-based learning approaches to teaching science, where the essential question is framed as a problem in need of a solution. Though there is as yet no consensus on the essential features of problem-based learning, one obvious element they all share is that student learning is oriented toward the development of a solution to a particular problem, with teachers serving as a resource as needed. Even though this approach is often quite group-based, one recent empirical study suggested that effective problem-based learning resulted from engagement with contextualized problems, more so than social factors arising from collaboration. This suggests that the choice of a good essential question has important consequences for student learning. One other function played by essential questions involves just-a-centered approaches to science teaching, sometimes called teaching science for social justice, that comes from a more critical tradition, and positions individual learners as actors engaged in a struggle for a more just society and human freedom. This just-a-centered approach to science teaching includes paying attention to how students can question assumptions and participate in ways that communicate their work products to a wider audience, a component that aligns well with current conceptions of scientific practice. In Grace's class, students invoked notions of justice in asking whether Henrietta Lacks sells would have been taken if she had been a white man, raising questions about race, gender, and the generation of scientific knowledge. As a class primarily comprised of students of color, this was not a theoretical concern. Here are some examples of good essential questions I have encountered over the past decade, working with teachers in science classes. What is the effect of hunting on the deer population in Wisconsin? When I shut off the light, what happens to the electrons in the wire? Should human cloning be allowed? How does a cell membrane know what to let pass? What counts as climate change? What is the impact of the nearby coal plant on the health of the people in the neighborhood? How does radiation both cause and cure cancer? Some essential questions are robust and perennial and can be used across multiple contexts and even grade levels. Others are more local and short-lived, particular to a time and place, and come carefully crafted from teachers who have studied their students' lives in school communities for connections to the subject matter. For example, one year when I was teaching physics, tragedy hit the community when a police car killed an elderly pedestrian during a high-speed chase, very near to the school. In the aftermath, the comment in the newspaper posed by a local resident struck me as a great essential question for the unit we were about to start on work and energy. Should high-speed car chases be legal? When I raised this question with my class, there was great interest, and though many students wanted to debate the legal dimensions of the question, I made room for the discussion because I had learned to recognize the importance of catching a wave of interest when one rolls in. Over the next month, as I taught a unit on work, energy, and the conservation laws, I would raise the police chase question every once in a while, adding to the physics at the heart of the question about when a chase was safe versus when it was unsafe. The big science idea concerned the relationship between an object's velocity and its kinetic energy, and how doubling the car's speed during a high-speed pursuit would quadruple the damage it could cause in a collision. Students had a chance to summarize their thinking about it in an end of unit essay, which confirmed for me that the essential question had served its purpose well. A good essential question accomplishes multiple ends. First, it provides students with a genuine problem. One whose answer is not apparent or easily discovered with an internet search, and encourages students' interest as a result. Second, an essential question connects to a big idea in science, even if it is not immediately obvious. Perhaps the most important function played by an essential question is that it serves as a touchstone to which the class returns as students progress through a unit. An essential question can be an explicit and ever-present part of the curriculum, but it can also be a filament of a theme that binds fragments of topics together and prevents science class from turning into a trivia game. Like the question Grace raised with her class, about what it even means to have rights over one's cells. The richest essential questions are the ones that have complex roots in the underlying disciplinary science, have implications for both teachers and students alike, and raise new questions as they are revisited over time. In Grace's class, these deeper questions emerged as students studied DNA, heredity, and mitosis. Was Henrietta Lacks herself still alive in those cells somehow? What does it actually mean for something, or someone, to be alive? While such questions may prove resistant to easy answers, they undoubtedly kindle the fires of inquiry in the minds of students, who, when provided with the scientific knowledge and tools by their teachers, continue to stoke them ever brighter.