- Common Sense Education
Common Sense Education has a section titled Ed Tech Ratings & Reviews that hosts teacher reviews and ratings for online games, websites, and apps. The site is free with no registration required.
- Core Knowledge Classic Lesson Plans
Free lesson plans for social studies for grades K-8. See my review of Core Knowledge Classic Lesson Plans.
- Federalist Papers and other primary source documents
free online access to the Federalist Papers and other primary source documents from the founding of the U.S.
- Historical Fiction for Children and Young Adults
annotated historical fiction recommendations arranged by time period, geographical, area, and reading level
- The Medieval Lifestyle article
useful article summarizing many areas of the medieval lifestyle: food, clothing, art, architecture, medicine, weapons, games, and entertainment
- The National Archives Experience: Docs Teach
This site makes primary source documents from U.S. history available and also provides extensive detailed lesson plans for teaching specific topics from U.S. history. Lessons cover only selected topics, so this is supplemental material.
- WatchKnowLearn Videos for History
WatchKnowLearn catalogs hundreds of free educational videos "Wiki-style" in both broad and sub-categories so it's easy to search. There are many sub-categories for history plus a separate section for Social Studies.