Hands-on activities can help elementary students understand how mountains are formed.
Learning about the movement of Earth's tectonic plates can be difficult for elementary students. These huge plates of Earth's crustal rock are constantly moving and changing the Earth's surface with enough force to move continents. Some 250 million years ago, the movement of tectonic plates broke up the supercontinent of Pangea to eventually form the seven continents we know today. Students can't feel the Earth move unless they experience an earthquake or live near a volcano. Using hands-on activities with familiar objects can help make the lesson more tangible and deepen their understanding of Earth's great forces.
When Tectonic Plates Meet
Explain to children the three types of plate boundaries. Tectonic plates collide and push together at convergent boundaries, causing earthquakes. Mountains and volcanoes were formed by tectonic plates colliding at convergent boundaries. A divergent boundary is where tectonic plates drift apart, causing rifts and valleys on Earth's surface. The Mid-Atlantic Ridge is an example of a divergent boundary. At a transform boundary, tectonic plates slide past each other, often causing earthquakes. These areas are sometimes called fault lines. The San Andreas Fault in California is where the Pacific plate and the North American plate slide past each other.
Tectonic plates occur on continents and under oceans. If an oceanic plate meets a continental plate at a convergent boundary, the less dense oceanic plate slides under the continental plate. Two continental plates colliding would form a mountain or volcano.
Drawing the Lesson
Direct students to copy a simple drawing you make on the chalkboard while explaining what happens when tectonic plates meet, diverge or slide past each other. The act of drawing keeps students more engaged than listening to a lecture or reading text. The visual aid helps them understand the relative size of tectonic plates and what happens on the Earth's surface. An added benefit to the drawing with the presentation is that students go home with a reference to the lesson learned.
Graham Cracker Exercise
Distribute graham crackers, cake frosting and plates to students. Have them put a thick layer of frosting on the plate.
Break graham crackers into four sections. Wet one end of one of the crackers. Place the wet cracker and the dry cracker end to end on the frosting-covered plate. Push them together and record observations. Have students ponder what kind of tectonic plate boundary this would represent. The correct answer would be a convergent boundary. The wet cracker represents an oceanic plate.
Place two dry crackers end to end and push them together. Record results and have students ponder what tectonic plate boundary this experiment would represent. This would also be a convergent boundary between two continental plates.
Place two crackers side by side and slide them past each other. Record results. This is an example of a transform boundary.
The Egg Experiment
Distribute hard-boiled eggs, a plastic butter knife and a plate to each student.
Tell students to consider the egg like the Earth, with layers. Instruct students to crack the shell of their eggs in several places. The cracked shell represents the tectonic plates.
Ask students to move pieces of the shell toward each other and observe what happens.
Cut open the egg for further exploration into the Earth's layers. The shell represents the crust. The white represents the mantle. The yolk is the core.
Tags: each other, past each, past each other, tectonic plates, convergent boundary