Instructional Video3:00
Curated Video

A Comprehensive Overview of Rulers

Pre-K - Higher Ed
This video provides an overview of rulers and their uses. It explains how rulers are used to measure distances and draw straight lines in various fields such as geometry, technical drawing, and engineering. The video also discusses...
Instructional Video
Khan Academy

Khan Academy: Where and Why Did the First Cities and States Appear?

9th - 10th
Fueled by surplus crops, agriculture led to the formation of the world's first large-scale civilizations. [10:45]