US Geological Survey
Usgs: Plate Tectonics and Mid Oceanic Ridges
Excellent graphics and understandable text about all aspects of plate tectonics including mid-ocean ridges.
US Geological Survey
Usgs: How to Build a Model Illustrating Sea Floor Spreading
This is a comprehensive website featuring how to build a model that illustrates sea-floor spreading and subduction. It has diagrams and pictures reviewing major geological concepts.
Institute of Marine Science
Forsea: If I Can't See It, How Do I Know It's There?
A diagram showing features of the seafloor and a laboratory experiment involving a model of the seafloor highlight this site. This is a good resource for teachers as well.
Concord Consortium
Concord Consortium: Seismic Explorer
Explore the pattern of earthquakes on Earth, including magnitude, depth, location, and frequency.
Science Education Resource Center at Carleton College
Serc: Hotspot Lesson: Hotspot Theory and Plate Velocities
Students use a data set of ages of Hawaiian Volcanoes and seamounts and how far they are from the active volcanism, and then plot the data on a graph, and finally determine the plate velocity.
CK-12 Foundation
Ck 12: Earth Science: Paleozoic Plate Tectonics
How plate tectonics formed Pangaea. [Free Registration/Login may be required to access all resource tools.]