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Jan 1, 2000 - Doing science involves both asking good questions and answering them. An interactive exercise to reveal more about the nature of questio...
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In the Classroom

Doing Science and Asking Questions: An Interactive Exercise Catherine Hurt Middlecamp* and Anne-Marie L. Nickel Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706; *[email protected]

What we observe is not nature itself, but nature exposed to our method of questioning. – Heisenberg

Doing science involves both asking good questions and answering them. An interactive exercise to reveal more about the nature of questions was developed in a graduate seminar on teaching chemistry (1). Here, we describe the exercise and how it was applied to a large introductory chemistry class. Overview of Exercise At the start of a semester, classes often begin by having students introduce themselves. The purpose of this exercise is to carry out these introductions and simultaneously reveal the ways in which questions can be constructed to collect data. To carry out the exercise, you need a room with plenty of space for writing, such as chalkboards or flip charts. The time required is 20–40 minutes, depending on the amount of discussion. Class Process 1. Present the exercise. Tell students that the class will start with “introductions”. Rather than having each person in turn introduce himself or herself, a different process will be used: everybody will answer the same questions and the class will analyze the data. To do this, the class first will generate these questions, writing them on the board so that each person can come up and check off his or her own responses. 2. Model the format. Tell students that they will construct the questions together, using a format where the responses easily can be tallied by counting check marks. Model the process by writing: Are you a

freshman sophomore junior senior

3. Refine the question. Questions may be incomplete or ambiguous. For example, the responses in the question just posed may not be sufficient to fit everyone present. To remedy this, categories such as “graduate student” or “other” may have to be added. As each question is asked, allow students to refine its wording as necessary. 4. Repeat steps 2 and 3. Ask students to continue generating and refining questions, slowly filling the board with questions. 5. At any time, allow discussion. Different issues can arise during the process of constructing questions. For example, after several questions have been constructed, students may complain about the rigid format, saying that they cannot find out what they want to know by checking a response. This is fine. It will lead naturally to a discussion of how the

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questions you ask (as well as which questions you ask) determine what you can find out. 6. Discuss the process of answering. Once you have generated sufficient questions, invite students to make rules about how to answer them. For example, decide if a person can mark more than one answer. Decide if everybody has to answer all the questions. Any rules are fine, but students should see that the rules chosen will influence the data. 7. Answer the questions. Have students leave their seats, pick up a piece of chalk, and check off their answers. If everybody does this at the same time, the process is fairly anonymous. 8. Invite student discussion. What do the responses tell us? Allow students sufficient time to make generalizations from the data before them. What don’t the responses tell us? For example, how did the format of the questions dictate what could be learned? What is gained and what is lost? Box 1. Some Questions Generated by Students to Introduce Themselves Why are you taking this class? ___ required ___ fun ___ schedule conflict ___ interested in chemistry

Do you enjoy chemistry? ___ yes ___ no ___ ?

Age ___ 18 and below ___ 18–21 ___ almost 18 ___ 21 and older

Do you plan to graduate in 4 years? ___ yes ___ no ___ ?

Are you going to grad school? ___ yes ___ no ___ who knows

How many parties did you go to last week? ___ 0 ___ 1–5 ___ 6–8 ___ can’t remember

Do you have pets? ___ dog ___ cat ___ rodent ___ fish ___ bugs ___ bigger ___ other ___ no

Do you have a significant other? ___ yes ___ no ___ ?

Journal of Chemical Education • Vol. 77 No. 1 January 2000 • JChemEd.chem.wisc.edu

In the Classroom

The Results Students quickly get the hang of constructing questions. They begin with fairly routine questions, such as age, academic major, home town, favorite sport, and why they are taking chemistry. Later, more complex questions may emerge, such as those relating to hobbies or marital status. Students may even wrestle with questions of sex, religion, and politics. Typical questions are shown in Box 1. Students critique and improve their questions. For example, in asking “How old are you?”, a variety of categories are possible. One class gave choices of 18, 19, 20, and 21+ years, forgetting that there might be younger students or returning adults. Another class designed categories with less resolution that spanned a greater range of years. The point worth raising is that the categories are arbitrary and many variations are possible, each of which can give you different data. Students also begin to explore the nature of their questions. For example, they may notice that different people ask different questions. If a different group of people had been their authors, the questions listed in Box 1 would address different concerns. Students also may notice that the format of the questions affects the data. For example, some information cannot be easily obtained through a “check off a response” format. Other issues may arise, such as, “Are some questions better than others?” or “Who gets to ask the questions?” In regard to the latter, instructors may wish to point out that questions can get missed for a variety of reasons. People may simply forget to ask them, the people who care about asking them may not be present, or the question itself may be incompatible with the format. This can lead to a discussion of questions that may not have been asked in science 100 years ago (Will this drug produce birth defects?), or are being asked more frequently today (Can I recycle this material?). As you debrief the exercise, you may want to contrast the chalkboard exercise with doing introductions by having each person introduce himself or herself in turn. The latter gives information in linear fashion, person by person. The former presents a composite of the class, but no data about the individual. It also gives data that can be tabulated numerically, for example, 60% of the students plan to attend graduate school. You might raise the question of whether numerical data are more “scientific”. Finally, note that this exercise gets the class off to an active start. On the first day, students start asking questions and cooperating to accomplish a goal. Their role in the course is evident from the outset—they can work together and by doing so may come up with better questions and more ideas. Related Classroom Activities Research in the sciences—physical, biological, social— depends on asking good questions. Students may have had some experience with the theory of questioning in their psychology classes, perhaps in the context of doing interviews or designing surveys. You may wish to refer to the social science literature to provide a theoretical framework for the design of questions (2) or the relationship between questions and critical thinking (3), or to provide explanations for what categories people form and how (4 ). As a textbook on social cognition points out, “Our perceptions of the world reflect

an interplay between what’s out there and what we bring to it” (5). Awareness of the subjective nature of our questions and the categories we use is important for all who do science. The same process of question design can be used to teach chemical concepts. For example, in the discussion sections of a large general chemistry class, we asked each student to select an element and look up its properties using one of the excellent periodic tables now available on the Web. In the next class, students constructed a set of questions (see Box 2) that would “introduce” the elements as a group, just as they had earlier introduced themselves as a group. Using their element as their identity, students marked answers to the questions on the chalk board that the group had generated. This exercise quickly helped students pinpoint useful questions to ask about an element. For example, the question, “What is its atomic number?” is of limited utility (e.g., it might be helpful to know that elements with atomic number greater than 82 are radioactive, but one doesn’t usually characterize elements by their atomic number). In contrast, the question, “What kind of an element is it?” is quite useful and can categorize elements as shown in Box 2 as well as in other ways. The question, “Is the element stable?”, caused a fair amount of discussion. Students confused stability in the context of radioactivity with stability in the context of chemical reactivity. This naturally led to a discussion of how the context Box 2. Examples of Questions That "Introduce" the Elements Atomic number of element ___ 1–20 ___ 60–80 ___ 20–40

___ >80 ___ 40–60

Date of discovery of element ___ antiquity ___ 1900s ___ 1700s

___ unknown ___ 1800s

What kind of an element? ___ alkaline earth ___ halogen ___ alkali metal ___ noble gas ___ transition element ___ other

What kind of an element? ___ metal ___ nonmetal

___ metalloid

Found in nature as ___ ___ ___ ___

an element a compound both don’t know

___ solid ___ liquid ___ gas

Properties of element ___ reactive ___ stable ___ corrosive

___ highly reactive ___ not reactive

Element is ___ stable

___ radioactive

Part of a living system? ___ yes ___ no

___ unknown

Is your element useful? ___ yes

___ no

JChemEd.chem.wisc.edu • Vol. 77 No. 1 January 2000 • Journal of Chemical Education

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In the Classroom

determines which questions you ask. In the case of elements, sometimes your questions focus on electronic properties; at other times they may deal with nuclear stability or toxicity. The issue of context can also be extended to other sets of chemicals later in the course. For example, given that “Chemical X” will be used in a lab experiment, what questions should one ask about it beforehand? How would the questions change if “Chemical X” were being considered as a starting material to manufacture plastic bottle caps, and you, the industrial chemist, were weighing its pros and cons? With question scenarios such as these, students can be taught useful questions to ask. For example, students may miss the question of how one disposes of a laboratory chemical or whether the plastic used for a bottle cap is recyclable. By situating “Chemical X” in a variety of contexts, students can learn how to vary their questions with the context. Additional References We have used this exercise for several years in a large general chemistry class. It has been used by one of us in workshops for faculty development, to spark discussion about the nature of questions in science. Predictably, the questions asked

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were different for each group of people (again illustrating the subjective nature of questions). Each time, however, the exercise worked smoothly and well, and participants reported favorably about what they had learned. A more complete analysis of this exercise can be found in Teaching the Majority, edited by Sue V. Rosser (6 ). Literature Cited 1. Middlecamp, C. H.; Moore, J. W. J. Chem. Educ. 1994, 71, 288–290. 2. Fink, A. How to Ask Survey Questions; SAGE Publications: Thousand Oaks, CA, 1995. 3. Browne, M. N., Kelley, S. M. Asking the Right Questions: A Guide to Critical Thinking, 3rd ed.; Prentice Hall: Englewood Cliffs, NJ, 1990. 4. Smith, E. E.; Medin, D. L. Categories and Concepts; Harvard University Press: Cambridge, MA, 1981. 5. Fisk, S. T.; Shelley, E. T. Social Cognition, 2nd ed.; McGrawHill: New York, 1991; p 99. 6. Middlecamp, C. In Teaching the Majority: Science, Mathematics and Engineering That Attracts Women; Rosser, S. V., Ed.; Athene: New York, 1995; pp 79–84.

Journal of Chemical Education • Vol. 77 No. 1 January 2000 • JChemEd.chem.wisc.edu