ASCD's Common Core Resources
ASCD received a $3 million grant from the Gates Foundation to support implementation of Common Core State Standards over a three-year period, and it has become an endorsing partner in the initiative. ASCD has developed a Common Core resource page with a wealth of information, and created a website called EduCore: Tools for Teaching the Common Core. The organization has a twice-monthly, topic-based newsletter, Core Connection (mentioned above), that you can subscribe to by filling out a brief survey. And there's a hashtag to follow on Twitter at #ASCDcore.
Common Core Toolkit from the Partnership for 21st Century Skills
Among all the great resources offered by the Partnership for 21st Century Skills (P21), you can find the Common Core Toolkit, a 48-page guide as a free PDF download or in hard copy for a nominal fee. This resource helps map the CCSS to P21's comprehensive Framework for 21st Century Skills. It includes lesson vignettes to show what such alignment looks like in action, resources and links for states and districts working to put the standards into place, and information about assessment.
Achieving the Common Core
As an independent, non-profit education-reform organization, Achieve has a mission of supporting standards-based education reform, and it offers both content and policy resources. The best place to start is the Achieving the Common Core page, where you will find a PowerPoint presentation, fact sheets, side-by-side comparisons of the CCSS and other respected benchmarks, videos, and lesson plans. The "On the Road to Implementation" guide is useful and well-organized, and Achieve has also developed a Toolkit for Evaluating the Alignment of Instructional and Assessment Materials.