Lesson-Planning Resources for the Social Sciences
The following link features social science lessons for grades K-6 (and beyond) written by teachers from all over the United States. Topics range from holidays around the world, recycling, ancient history, and Westward expansion, among others. Lesson structure comprises objectives, materials, procedure, assessment and evaluation, and modification and differentiation, along with related lesson plans.

https://www.teacher.org/lesson-plans/social-studies/

Lesson-Planning Resources for History
This "Best of History Websites" portal from edtechteacher features categorized and annotated lists of links to hundreds of K-12 history lesson plans, teacher guides, activities, games, quizzes, and more to be adapted to individual classrooms. Check the sidebar for resources ranging from pre-history to history today. Scroll down farther on the sidebar for resources on lesson plans, social sciences, geography, maps, and games and animations.

http://www.besthistorysites.net/index.php/lesson-plans

Lesson-Planning Resources for Geography
Click the link for standards-based geography lesson plans developed by the Geographic Alliance of Iowa for students in grades 3-5.

https://gai.uni.edu/lesson-plans-and-curricular-materials/3-5

Get ideas for what to include in your geography lesson plans with JumpStart's collection of geography activities

(http://www.jumpstart.com/parents/activities/geography-activities) and worksheets

(http://www.jumpstart.com/parents/worksheets/geography-worksheets) for elementary-level students.