US Geological Survey
Usgs: Understanding Plate Motions
The U.S. Geological Survey provides descriptions and illustrations for the plate boundaries of the Earth's surface.
Science Education Resource Center at Carleton College
Serc: Hawaiian Islands: Volcano Ages, Hotspots and Plate Motion
The ages of volcanic rocks are used to investigate speed of motion of the Pacific plate, to analyze the distinctive bend in the chain, and to consider the age data in the context of a hotspot model of formation.