In this role-play students take on the roles of scientists attending a symposium in the early 1960's.  They discuss the feasibility of continental drift applying evidence available in the 1920's, and adding new information gained from seismic, sonar, drilling, and paleomagnetic studies.  Each group presents the results of its research.

ENGAGEMENT

Day One

The teacher sets the scene.  The year is 1963.  Since the publication of Wegner's book in 1924, scientists have been looking for evidence that might support or contradict his idea.  Eight groups from all over the world are meeting to present the results of their research and to discuss the newly emerging theory of plate tectonics.  The spokesperson for each group is a leading scientist, but he or she is accompanied by research assistants who helped with much of the work.

It may be helpful to prepare a folder of resources in advance to give to each group.  This contains
 

• A copy of the briefing sheet with a note-taking guide on the reverse (for use when students give their presentations).
• Role-playing guides

Americans	Brazilians	Greeks	Soviets
Indians	Germans	Poles	Japanese

• Overhead projector transparencies.
• Props for the person leading the group (such as tie, hat, scarf, shawl, Geiger counter, rocks, use of accents, etc.)

EXPLORATION

Allow students time to prepare their presentation.  This time may be spent making reading their briefing sheets, transparencies, gathering props, making lists of what will be said, researching their country in an Encyclopedia, decorating folders, etc.

Day Two

During role-play, students are typically asked to take on a relevant role and then to prepare and prsent an argument relevant to a particular issue.  Remind students to use their knowledge and understanding of the science that is relevant to the particular issue so that their arguments will be meaningful.  Give suggestions on working collaboratively to develop an argument, clarity of presentation, respect for the views of others, etc.

When the symposium begins, each group in turn describes the research it has done and the results of its work.  Allow about 20 minutes for this.  Some presentations will be very short, others will take longer.  Allow students to ask questions if more explanation of a particular topic is needed, but make sure they do not begin the discussion of Continental Drift until all the papers have been read.

The Americans can be led by a fictional Dr. Wegener, descendent of the notable Dr. Alfred Wegener of continental drift fame.

In the second part of the symposium, evidence for and against the plate tectonics is weighted in the light of what students have just heard.  They must, in their roles as scientists, decide whether the theory of plate tectonics is a feasible one.  What is different about this symposium from the 1926 one is that now scientists have a mechanism to support the idea of continental drift.

Today, this theory is perhaps the biggest idea in geology.  However, allow students to come to their own conclusions.  If the debate lasts about 10 minutes, there should be time at the end of the lesson to hand out abstracts from the syposium.  These provide a record of the proceedings and, for the students, give a useful summary of the evidence.

Day Three

EXPLANATION

The Review Sheet (with symposium abstracts on the reverse) recounts the story of what happened at numerous symposia and conferences throughout the world in theearly 1960s.  It reviews why the theory of Continental Drift was virtually forgotten for many years, even though the evidence for the existence of one "super-continent" was so strong.  The second theme in the Review Sheetis that of the nature of scientific discovery, and the ways in which scientists communicate their findings to one another.

ELABORATION

Students are asked to write a conclusion to their own symposium and to compare it with that arrived at by the geologists in the 1960s.  They can then list ways in which scientists gather information.
            
EVALUATION:

Answers to Student Sheet:

1. The students' answers should include the following:

• Mountains form when continental plates collide, and from volcanic activity associated with the friction from plate subduction.
• Volcanoes form when one plate subducts beneath another, the subducted plate melts, and the less dense magma rises to the surface. Additionally, students may mention the volcanic activity associated with rifting or with hot spots (plumes).
• Earthquakes form when plates move, due to the stick-slip nature of their movement.

2. Diagrams should be complete and labeled.

3. Ideas would not be shared, and large-scale theories would not develop.

4. Students will hopefully argue that plate tectonics qualifies as a theory: it is a natural explanation; it incorporates a vast amount of experimental data; it is logical.
 

Updated June 25, 2001