This portal provides links to selected United States Geological Survey (USGS) educational resources that may be useful to educators in primary school grades. Many of these resources can be used directly in the classroom or will be useful in classroom lessons or demonstration activities preparation, or as resources for teacher education and curriculum development. Major topic areas include biology, geography, geology, and water resources. Resources (indicated by symbols) include complete teaching modules, classroom activities, and web-based resources. Items that have costs beyond basic printing or on-line viewing costs are also indicated by a symbol.