| Group activity
Supply groups of students with a hard boiled egg, a leather soccer ball,
a globe, and cutout shapes representing each of the continents.
As in any group situation, encourage
students to work cooperatively during the tasks. Assign people in each
group to be responsible for manipulating equipment, observing, recording,
and reporting. Ask students choose different roles during subsequent activities.
Emphasize that each of the objects
they have acts as a model to help understand continental drift. Ask the
groups to create analogies that show how each object can represent the
Earth.
The hard boiled egg has a thin
outer shell. This is analogous to the Earth's crust. The egg white represents
the mantle, and the yolk the core. By cracking the shell, students might
convey the idea that the crust can be thought of as consisting of sections,
rather than continuous, undisturbed matter.
The soccer ball can reinforce that
concept about the Earth's crust. The sections of the ball are all joined
together. These are analogous to the plates on the crust.
The globe provides a reference
for considering the other objects. If the globe has relief contours on
it, those might indicate where regions of the plates meet, similar to the
boundaries between two connected patches on the soccer ball.
Finally, the shapes of the continents
can reinforce the idea of continental drift. Have students arrange the
continents on a surface, using the globe to place the shapes in their relative
positions. Ask them to try to move the continents together, as if they
were moving the pieces in a large jigsaw puzzle until they find the best
fit. Once they have the best fit, have them slowly return the continents
back to their original position, noting the direction that each one moves.
According to the theory of continental drift, forces within the Earth cause
the continents to move in this way, . |
