NEW NSDL 2006 Annual Report

The National Science Digital Library’s 2006 Annual Report was released at the American Association for the Advancement of Science Annual Meeting earlier this month. The report highlights the multiple roles that NSDL plays in support of STEM education that include providing a resource repository, services, tools and activities for teacher professional development, education and outreach opportunities, a locus point for digital library research, and collaboration opportunities for scientists and educators. Focused on NSDL as the hub of an expanding network of partners, projects and initiatives, the report looks to a future NSDL that leverages strong NSDL 2.0 technical and social components to “create a critical mass of value” as a key part of the nation’s educational cyberinfrastructure.

Download a copy of the 2006 Annual Report here: http://nsdl.org/publications/?pager=ar, or request single or multiple copies by contacting Donna Cummings at .

BEN–NSDL Biological Sciences Pathway–Launches New Portal
http://www.aaas.org/news/releases/2007/0226ben.shtml

The new BiosciEdNet (BEN) Collaborative portal features easier-to-use advanced search functions enabling educators to sort the more than 4,700 reviewed resources covering 77 biological sciences topics into grade-level categories. In addition, the new site will allow searchers to limit results to free resources.

Besides layout and navigation updates, the Collaborative selected 21 undergraduate faculty members to become the first cohort of BEN Scholars. With the mission of providing grassroots outreach for the digital library and inquiry-based learning in higher education, the Scholars will promote the portal on their campuses and contribute materials to the digital library.

Assigning Grade Levels to NSDL Resources
Charles Cowart, Bing Zhu, and Reagan Moore, San Diego Supercompter Center (SDSC), have developed a Grade Level Assessment Service (GLAS) for use with NSDL resources. Since 2002 SDSC has been an NSDL partner in developing the technical infrastructure to create a “memory” for the Library through long-term archiving services. The new GLAS service associates a grade level with each word used in an online resource. If 99% of the words are from say, the sixth grade level or lower for example, the resource is assigned to the 6th grade.

The dictionary used for the grade level analysis at SDSC was composed through an iterative approach. Starting with an initial dictionary with 5,514 words representing grade level vocabularies for kindergarten through the 6th grade. The material was characterized in a crawl of the NSDL URLs. Each URL was then assigned a grade level, allowing 1% of the words to be from a higher grade level. Researchers then looked at the 1% of the words that appeared from higher grade levels that were present in the material, and reassigned the words to lower grade levels when appropriate. So far 5 assessment iterations have been conducted. The total number of words that are now recognized by grade level is 4,994,883. The number of words associated with grade levels from kindergarten through high school is much smaller–71,095 words. Many of the words in the extended list represent technical terms, or common miss-spellings.

A sixth iteration of the grade level analysis is in progress. The tasks for analyzing the NSDL material (3.3 million HTML files and 1.2 million text files) are executed in parallel on the Teragrid computer at SDSC. For each crawled website, the output of the analysis is the number of words in each grade level from 0 to 16, where 0 stands for kindergarten and 16 for college. The results are published through the GLAS service, with each URL assigned a grade level that is consistent with the vocabulary used within the material at that web site.

The Grade Level Assessment Service (GLAS) is based on the OAI-PMH 2.0 specification. It supports incremental harvest, the NSDL extended Dublin Core metadata schema, and NSDL’s education level element set. Contact Reagan Moore for more information .