National Park Service's WebRangers
"This is the National Park Service's site for kids of all ages. If you love our National Parks, Monuments and Historic Sites, this site is for you. If you are new to our National Parks, we hope this site helps you experience how wonderful they can be."
"The WebRangers Teacher’s Resource Guide allows teachers to quickly assess more than 50 WebRangers activities and discover how each activity meets National Standards of Learning. (Common Core alignments will follow.) Here, educators will be able to read a brief description of each activity and understand how each activity addresses a breadth of subjects including geography, history, language arts, math, science, and social studies."