There are three main processes of coastal erosion. Hydraulic action is the power of the waves crashing into the cliffs. This forces air between cracks in the rock, breaking it apart. Corrosion/solution is the process of chemicals in sea water, such as salt, dissolving minerals in the rock. Corrasion/abrasion is the weakening of the rock by sand, shingle and other particles carried in the sea.
Students should create annotated diagrams explaining each of the processes of coastal erosion. This can then be expanded on when considering case studies, fieldwork excursions or map interpretation exercises.