Announcement: The operation of NSDL has been transferred to ISKME's OER Commons (effective December, 2014) - Read the news release.
This documentation describes the policies, procedures, and services that existed while NSDL was operated by UCAR.
The Search API provides the ability to search for resources in the NSDL digital library and build customized search and browse interfaces for a variety of applications. Search queries access metadata stored in the NSDL repository, including resource metadata, annotations, and use data/paradata. The Search API is based on an index of terms, compiled and accessed using the Lucene search engine. The API provides a resource-centric view of the repository, that is, for each resource (URL), Search operates over and can return all associated metadata, annotation, and use data/paradata records associated with the resource in a single search hit.
The API is implemented with an instance of the the Digital Discovery System (DDS) repository search server.
The new Search API went into production at the beginning of April, 2011, replacing the previous NDR Search API. The NSDL.org web site, partner sites and learning applications began using the new API at that time.
The API base URLs is:
For historical reference, see the previous NSDL Search API documentation (API deprecated April, 2011).