Earth Stories: Earth Science for Elementary Education Majors

71-150

Students enroll in one course that includes both lecture and lab. The lecture is taught by the professor and the lab is taught by TAs.

The course catalog designation of this class is Physical Science 110B (PS 110B). Nearly all the students at the university are required to take PS 100, a 4-credit basic science course, but Elementary Ed. majors have additional requirements that can be satisfied in one of two ways. 1) They can take PS 110A (4 credits, covers physics and chemistry) and PS 110B (2 credits, covers basic geology) instead of PS 100. Both PS 110A and 110B include a lab component. 2) They can take PS 100 in addition to both PS 111A and 111B, which are 1 credit lab courses. In fact, PS 111A and 111B students meet in the same lab sections as the PS 110A and 110B students. This makes it rather difficult to to design the PS 110A and B courses for El. Ed. majors so that the lab and lecture mesh perfectly.

There are no prerequisites for this course.

1. Students will be able to explain what science is, and why science is done the way it is. To do this, you will have to learn how scientists think.
2. Students will be able to explain basic earth science concepts in terms of fundamental physical and chemical processes.
3. Students will be able to explain (in general terms) the history of the Earth, or particular features of the Earth, using correct scientific vocabulary.

Students will be able to identify and debunk common misconceptions about Earth science.

Teaching the Process of Science

The overarching philosophy I bring to the class is this: If our intent is to teach students how science is done in the context of an introductory class, we can't just expect them to "discover" this process via lab experiments, etc. These are good for what they are, but it is extremely hard (and time-consuming!) to provide really authentic experiences of actually "doing science" for students at this level. Even if we come pretty close to authenticity, most students won't pick up on the subtle points about the process of science unless they are explicitly pointed out along the way. Therefore, we need to explicitly teach students some basic history and philosophy of science along the way. (See Abd-El-Khalick and Lederman, 2000, Journal of Research in Science Teaching 37, 1057-1095.)

Following are some examples of how I try to incorporate this philosophy into my class.

1. I start the course with a unit on the Nature of Science (NOS) called "Science as Storytelling." This is designed to help students overcome a number of misconceptions about the NOS, especially the idea that good science is "just the facts." The "storytelling" label puts them on notice that I'm not just going to tell them about the "scientific method" they learned about in Jr. High, and it also helps get across the idea that the NOS includes creative and tentative, in addition to empirical, elements. This unit was described in more detail on the Science as Storytelling activity page. The "Science as Storytelling" essay that students are required to read for this unit is included in the course pack linked below.
2. They complete the Ordeal by Check lab activity.
3. We next cover a "Cast of Characters" unit. The idea here is that geologists use the basic physical and chemical principles sort of like characters in our stories. When we want to explain how some present geologic feature came to be, etc., we employ concepts like gravity, density, buoyancy, heat transfer, deformation of solids, PTX control of chemical reaction, and so on, as the actors who do all the work. We go over these basic principles, targeting common misconceptions.
4. Later in the course we keep referring back to the "Cast of Characters" as we construct our explanations for geological phenomena. The reading for this unit is also included in the course pack included on this page.
5. When we cover rock classification and identification, I constantly emphasize that geologists chose these particular classification schemes based on certain characteristics of the rocks that tell us something about how they were likely to have formed. So, if a kid in your elementary school class comes to you with a rock that you identify as rhyolite, you automatically should know quite a bit about how that rock formed. (It's igneous, so it formed as molten rock cooled and crystallized. It's felsic in composition, so its minerals have lower melting temperatures than those in more mafic types of igneous rocks. Thus, the magma it came from probably originated at a relatively shallow depth in the crust. Its texture is aphanitic, so it had to have cooled and crystallized very rapidly. Thus, it must have formed at or near the surface in a volcanic system. Since felsic magmas are relatively cool and silica-rich, they tend to be more viscous, which helps them retain gas bubbles more effectively. Thus, volcanoes with felsic magma tend to explode more violently. The list could go on....) The point is that nobody cares whether they can put a name on a rock. But if they can use their rock identification skills to construct basic geologic interpretations, then maybe it's something worth knowing.
6. When we cover a unit on Plate Tectonics, I approach it from a historical perspective. We go over "Contracting Earth" theory--what it was meant to explain, and newer observations that were problematic. We then go over Alfred Wegener's evidence for his Continental Drift hypothesis and discuss why the vast majority of geologists rejected it. (CAUTION: Almost every introductory geology textbook ever written is flatly wrong about this point--i.e., they say that no plausible mechanism for continental motion had been proposed until Plate Tectonic theory came into vogue. But Arthur Holmes published a possible mechanism--convection currents in the mantle--way back in 1929, so clearly the textbook explanation for the rejection of Continental Drift is fanciful. If you really want to know the historical situation, read Naomi Oreskes, The Rejection of Continental Drift: Theory and Method in American Earth Science, Oxford University Press, 1999.) I have the students vote on (using "iClickers") and discuss various questions, such as whether the geologists who rejected Wegener's hypothesis were being reasonable. The moral I draw out of all this is that theory choice isn't always that simple. Should we keep the old theory that is useful in many contexts and try to fix it up to explain new observations? Or should we abandon ship and go with a new type of explanation? Questions like these cannot be decided completely in rational terms.
7. I also do activities (described in the Observations vs. Explanations activity) in class to help students understand the distinction between scientific observations and explanations. A surprising number of them are really confused about this, and you can't make much progress in teaching them scientific thinking skills until they get over it.

The following assessment strategies are numbered to go along with the Course Goals listed above.

1. I ask specific quiz and test questions about the NOS, targeting common misconceptions, and others that are designed to test student understanding of how scientists came to particular conclusions. I also ask them questions that require them to connect several concepts together to construct geologic explanations.
2. I design questions to test whether students understand the links between explanations of geologic processes and the basic physical and chemical principles in their "Cast of Characters".
3. I ask test questions about this kind of standard stuff, as well, and have several corresponding lab activities.
4. I specifically target common misconceptions when designing test questions.

Earth Stories (Acrobat (PDF) 1.6MB May28 09)

Lab Manual (Acrobat (PDF) 686kB May28 09)

Foundations of Earth Science, Lutgens and Tarbuck
This is only a 2-credit class, including a lab. I needed a textbook that covers some basic geology without being gigantic. I don't even cover the Oceanography and Meteorology portions of the book.
I have my own lab manual.