The National Science Digital Library (NSDL, officially the National Science, Technology, Engineering, and Mathematics Education Digital Library) is a national network of online learning resources and organizations dedicated to the enhancement of science, technology, engineering, and mathematics (STEM) education at all levels in both formal and informal settings.  For more than ten years, NSDL has been active in the aggregation, contextualization, and dissemination of digital learning content generated through NSF grants and other  federal agencies, as well as non-profits such as museums, research labs, and professional societies.

NSDL launched the STEM Exchange as a means to mobilize content into the hands of educators through online communities, and to establish return feedback loops of data created by the activities of communities around that content—a type of data we have defined as paradata, adapting the term from its application in the social sciences.  The concept of learning resource paradata is grounded in the premise that teachers trust teachers to understand and inform what might be most useful to a particular pedagogical context.  Paradata provides a mechanism to openly exchange data about how resources are discovered, assessed for utility, and integrated into the processes of designing learning experiences. Each of the individual and collective actions of favoriting, foldering, rating, sharing, remixing, embedding, and embellishing that are the hallmarks of today’s teacher workflow around digital content are points of paradata that can serve as indicators about resource utility and emerging teacher practices.

To accelerate the diffusion of content to education practitioners, the NSDL STEM Exchange has shared its underlying concepts and ideas to seed the development of the Learning Registry, and is one of the first Registry collaborators to contribute and consume metadata and paradata using this critical new set of tools and technologies.  With  partners Butte County Office of Education / Center for Advancement of Digital Resources in Education (BCOE/CADRE) and Navigation North Learning Solutions, NSDL’s STEM Exchange became the basis for the first proof of concept use case for the Learning Registry.

NSDL STEM Exchange shares metadata and/or paradata to the Learning Registry about resources from content providers including:

AAAS Project 2061AMSER: Applied Math and Science Education Repository


CLEAN: Climate Literacy and Energy Awareness Pathway

CSERD: Computational Science Education Reference Desk

ChemEd DL


Concord Consortium


CTE Online

DLESE: Digital Library for Earth Systems Education

Dragonfly TV

Education Development Center

Engineering Pathway

Ensemble Computing Pathway



Instructional Architect

  Math Common Core CollectionMaterials Science Digital Library


Math Landing

MSP2: Middle School Portal Social Network


National Science Foundation

National Science Teachers Association



Science Refreshers

SMILE: Science and Math Informal Learning Educators Pathway

Teach the Earth

Teachers’ Domain


U. S. Department of Energy