Instructional Video21:16
TED Talks

TED: An 8-dimensional model of the universe | Garrett Lisi

12th - Higher Ed
Physicist and surfer Garrett Lisi presents a controversial new model of the universe that -- just maybe -- answers all the big questions. If nothing else, it's the most beautiful 8-dimensional model of elementary particles and forces...
Instructional Video14:46
msvgo

Equivalence Relations and Classes

K - 12th
It explains the conditions for a relation to be equivalence relation through solved examples. It also explains equivalence classes and provides examples based on it.
Instructional Video
Khan Academy

SAT Prep: Test 2 Section 9 Part 3

9th - 12th
Carefully reading word problems is a skill that many students neglect due to time constraints or test anxiety, and Sal models how to do so in this video. Both algebra and geometry are featured in problems 10-12 of the practice SAT.