In 2016, The US National Park Service turns 100 years old. As the National Park system approaches that centennial, the biodiversity of the parks remains greatly unknown and at the same time, park visitation is declining. This session will examine the increasing popularity of citizen science in parks and protected areas and describe the first national inventory of the parks using citizens. All Taxa Biodiversity Inventories (ATBIs) use citizens as parataxonomists, working in concert with taxonomists and managers. ATBIs tend to focus on the untapped diversity in non-vascular plants and invertebrates and citizens work at the basic levels to help collect, sort, and identify specimens. The National project focuses on using the established popularity of bioblitzes - one day events using citizens to collect specimens - as a starting point to examine not only what the biodiversity of a protected area is, but also how citizens get involved with the discovery of new organisms. We are particularly interested in whether such activity helps develop a sense of stewardship. Seventy-two parks have been selected as part of this pioneering project. Each phase of the project has two elements: the social aspect (why citizens participate) and the biotic aspect (what is biodiversity and how is it described). Our main discussion will revolve around developing citizen scientists as parataxonomists while discovering the biodiversity of US National Parks.