Arbor Day was first observed in 1872, and the Arbor Day Foundation was founded in 1972 in Nebraska. The Arbor Day website contains a trove of information for visitors to peruse, make plans around, and learn from. The "Trees" section of the website includes "What Tree is That?", an online guide for tree identification; a "Tree Guide", that covers more than 200 different species of trees; and a quiz called "The Right Tree in the Right Place", about how and why to first make a simple plan, considering size and shape, when planting trees around a house. The "Programs" section of the website is an excellent resource for visitors such as teachers, parents and students. "Nature Explore" helps connect kids with nature via the "Resource Guide", which contains "field-tested resources developed to bring nature into children's daily learning in sustainable, significant, positive and joyful ways." Interested visitors can use the link entitled "Request a Resource Guide", to get a free copy. "Nature Explore Classroom Certification" links teachers to the certification process and examples of certified classrooms and classrooms in-progress.