Video: Common Core State Standard (CCSS) 8.EE.B.5 Expressions & Equations Proportional Relationships, Lines, and Linear Equations Graphing Proportional Relationships With Unit Rate and Slope (Grade 8)
Here is an asset that is currently on PBS LearningMedia. It is a good "activating" segment to get students to think about the meaning of slope in everyday situations before actually computing slopes of linear relationships. This video captures a clear understanding of the concept and serves as a real world example embedded with mathematics.
What IS important is how the math is visualized in any entry.
What is NOT as important is how "professional" looking the video entries are.