Build the restless-crust idea through modelling with hands and whole-body plate movements.
Be the plates
Students model plate boundaries with their bodies. Two lines of students press palms together and push — then suddenly slip past each other to feel a quake's "stick and slip". For a volcano, students crouch as "magma", then rise and burst upward through a "vent" gap as pressure builds. Feeling the sudden release makes the cause concrete.
Layered clay Earth
Deepen the clay activity: students build the four layers in concentric balls (yellow inner core, orange outer core, red mantle, thin brown crust), then slice it with dental floss to reveal the cross-section they'll label. Making and cutting the model fixes the layer order by hand.