Chemical Education Today edited by
Erica K. Jacobsen Associate Editor, Precollege Chemistry
Laura E. Slocum
Predictions and Explanations
Assistant Editor, Precollege Chemistry
Laura E. Slocum* and Erica K Jacobsen
As this school year started, I found myself at a crossroads that I know many of us find ourselves at during various times in our teaching careers, asking myself this question, “How many changes do I really want to make in my curriculum this year?” I had actually been asking myself that question all summer and I had a variety of answers mapped out, but I was not sure what changes my chemistry teaching colleague would be comfortable making when he and I finally talked just a couple of weeks before classes began. At my school, when my colleague started teaching chemistry last year, we made the decision to teach out of the same book, at about the same pace, use the same labs and to use the same approaches in some areas. So, because I was considering some pretty big changes to my curriculum, I knew we both needed to be ready to make these changes. He was even more excited than I was to incorporate these changes. This summer, I attended a weeklong workshop, “Modeling Instruction in High School Chemistry” in Indiana (1) that I really liked. Modeling instruction is a student-centered instruction approach in which students work in small groups to collaborate and answer questions and then share their answers in oral or written formats. The questions the students are answering could be related to a demonstration, laboratory work, or a homework assignment. I felt this approach would be much more engaging for our students. So, as my colleague and I discussed what I had learned, we made a list of our predictions for the students and said, “Let's see were the students are, based on our predictions for them and this teaching model, after the first month.” We started the school year using the modeling instruction approach across our whole chemistry curriculum. The students exceeded our predictions for them. Even those students that openly dislike science are trying more than we have ever seen them try in the past. Things across the entire curriculum are not 100% better, but that was not our goal. Engaging students more verbally, thoughtfully, and in hands-on activities are part of the main goals for incorporating these changes to the curriculum. Why do we think this is happening? The students say it is because, “we get to talk more about what we know”, “we get to ask more questions”, and “we get to do more hands-on activities”. My colleague and I agree on all of these things, but we also think it has to do with the order in which topics are being taught. This transition has not been a simple one for us and we will not really know how the students do on the whole chemistry curriculum until the end of the course when they take the ACS First-Year Chemistry Exam, as we have had our students do for the past 10 years. Because we are definitely seeing more engaged students, we are quite encouraged as teachers. However, it has been a big change for us both, as well as a lot of work for us too. I will keep you posted on our thoughts about the modeling instruction 1282
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approach when the school year draws to a conclusion. So far, we like what we are seeing in our students! Not only are we as teachers making predictions and then providing explanations about our students as we assess them, but our students are doing the same thing within the course. Gil and Paiva describe a number of the techniques we have used in their article, “Questions and How To Differentiate Prediction and Explanation in Chemistry Teaching and Learning” (DOI: 10.1021/ed100531b). In particular, they focus on the idea that “the encouragement of questions by students in the teaching and learning of chemistry requires a proper distinction among the different types of questions. In particular, it is important to distinguish between `fundamental whys' and `operational whys'.” As I read through their article, I came to really appreciate their differentiation of these two types of “whys” and how it applies in my course. An example of an “operational why” for me is connected to what I ask my students to do in the lab. To date, with the exception of one lab, my first-year students have been asked to make predictions about what they expect to observe or discover in a given lab. I had not previously been doing this in every lab. As they complete their lab reports, they are then asked to assess their predictions and explain any differences between what they observed and what they predicted. We have already had a discussion in class, either as a whole class or in small groups, so the students are not being asked to make random “guesses” on their own on their lab reports. Loyson's article, “Influences from Latin on Chemical Terminology” (DOI: 10.1021/ed1000894), reminded me of being back in high school and taking a course on Greek and Latin derivatives. I really liked that class a lot and learned more vocabulary in one semester than I think I have ever learned. That class helped me in my first career as a respiratory therapist and now as a chemist. I know my students sometimes comment, “Chemistry is like a foreign language; there are too many new words.” If they only knew how all the words were connected, I do not think it would seem that way to them. We offer an etymology course at our school and the students that take it love it and say it is really helpful to them. Those in my chemistry class that have had this course often seem a bit more comfortable with the language of chemistry. Erica's Take on the Issue Every so often, as I read through an issue of JCE, a particular article will bring to mind the old saying “You can't judge a book by its cover.” In the case of an article, the saying could be revised to read “You can't judge an article by its title.” Part of writing an effective article for a professional publication includes an
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Vol. 87 No. 12 December 2010 pubs.acs.org/jchemeduc r 2010 American Chemical Society and Division of Chemical Education, Inc. 10.1021/ed1009514 Published on Web 10/14/2010
Chemical Education Today
Figure 2. Close-up view of (A) Cubic copper crystals; (B) dendritic copper crystals. Reprinted with permission from ref 2. Copyright 2009 National Science Teachers Association. Figure 1. Steve Long's article “Highlights from The Science Teacher: December 2009 to Summer 2010” mentions a copper crystal growth experiment. Shown is an example setup for the lab. Reprinted with permission from ref 2. Copyright 2009 National Science Teachers Association.
informative, yet not overlong, title. Reading through the titles in JCE's table of contents can give educators a clear picture of the overall issue, including possible thematic threads, and can quickly alert them to what they might be interested in reading. Sometimes, even though an article's title is completely clear and up front about its content, it can be beneficial to look beyond it. In certain cases, reading about something that is outside of our own sphere, while being open to thinking outside the box, can lead to making connections with our own curriculum topics and grade levels. This month's example for me was “Customized Laboratory Experience in Physical Chemistry” (DOI: 10.1021/ ed1005097). Depending on one's college experience, one might inwardly shudder at even browsing a title containing the phrase “physical chemistry”. But I was intrigued by what this article had to offer about how one might customize a laboratory experience, in order to put “more control into the hands of the students without sacrificing the rigor or thoroughness of a content-driven laboratory.” Students are asked to select and complete seven experiments within nine weeks of laboratory work, including at least one experiment from each of five categories, then report on them using a combination of full and mini lab reports. One benefit is that it allows students to focus on a particular area that interests them and performing more than one experiment related to that topic. In my oldest daughter's homeschool science coursework this year, her text offers this experience. There are far too many experiments to cover in the time allotted, so for each week's topic, she selects two, based on her interest. Admittedly, most of the experiments do not have a time-intensive setup, and is made easier with only her and two siblings participating. But, could this model be extended to the high school chemistry classroom? Are there any out there who have based their
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laboratory on this model? Is it even possible for a teacher to have time for multiple labs, because of some of the advance setup that cannot be performed by students? This month brings another installment by Steve Long (DOI: 10.1021/ed100890u), offering highlights from the past several issues of The Science Teacher (TST), and connecting them with JCE resources. For example, Steve describes a copper crystal growth experiment from TST, which can be useful for teaching redox concepts; see Figures 1 and 2. A search on the JCE Web site reveals that Steve has written 20 such articles for this feature, beginning in 1998. He and I spoke at a summer conference this year, and he wondered about the possibility of finding a high school teacher who is a reader of both TST and JCE. Then, Steve could continue to offer his insight in one article a year, with another contributor taking on a second article for the year, with a view toward maybe finding someone to eventually take over the position. Please let Steve (
[email protected]) or me (
[email protected]) know if you have an interest in such an opportunity. Steve can tell you more about how he puts a column together, and the time commitment involved. Precollege Chemistry Featured Articles 6Mbindyo, J. K. N.; Brown, A. Investigating UV-Blocking Properties of Sunscreens on the Microscale. J. Chem. Educ. 2010, 87 (DOI: 10.1021/ed1004504). 6Gil, V. M. S.; Paiva, J. C. Questions and How To Differentiate Prediction and Explanation in Chemistry Teaching and Learning. J. Chem. Educ. 2010, 87 (DOI: 10.1021/ed100531b). Literature Cited 1. Modeling Instruction in High School Physics, Chemistry, Physical Science, and Biology. http://modeling.asu.edu/modeling-HS.html (accessed September 2010). 2. Corcoran, T. Grow Your Own Copper Deposits. TST 2009, 76 (9), 43–46.
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