The document discusses plate tectonics and provides information about the 15 tectonic plates that make up the Earth's surface. It explains that the Earth's crust and upper mantle form tectonic plates that fit together like puzzle pieces. The places where plates meet are called boundaries, and volcanoes and earthquakes often occur at these boundaries as islands, mountains, and ocean trenches form. Students are provided the names and numbers of the 15 tectonic plates to use in completing a plate tectonics puzzle activity.