Where can I find this video?

Yes, she is Alexis Texas in Cheerleaders from Digital Playground.
http://covers.data18.com/1/123605-cheerleaders-front-dvd.jpg
http://covers.data18.com/1/123605-cheerleaders-back-dvd.jpg

Trailer
http://www.dvdtrailertube.com/Cheerleaders--Blu-ray-Disc-Digital-Playground-trailer-12748.html

The video you are looking for is this one:
http://www.dailymotion.com/video/x1yv0lz_beautiful-girl-showing-ass-to-class-teacher_redband

Scene 1
Jesse Jane with Manuel Ferrara.



Scene 2
Memphis Monroe with Erik Everhard and Mick Blue.



Scene 3
Adrenalynn and Shawna Lenee with Johnny Sins.



Scene 4
Alexis Texas, Camryn Kiss and Shay Jordan with James Deen, Johnny Sins and Tommy Gunn.



Scene 5
Brianna Love and Stoya with Manuel Ferrara.



Scene 6
Adrenalynn, Brianna Love, Jesse Jane, Lexxi Tyler, Memphis Monroe, Priya Rai, Shay Jordan, Sophia Santi and Stoya.

Yes, she is Alexis Texas in Cheerleaders from Digital Playground.
http://covers.data18.com/1/123605-cheerleaders-front-dvd.jpg
http://covers.data18.com/1/123605-cheerleaders-back-dvd.jpg

Trailer
http://www.dvdtrailertube.com/Cheerleaders--Blu-ray-Disc-Digital-Playground-trailer-12748.html

The video you are looking for is this one:
http://www.dailymotion.com/video/x1yv0lz_beautiful-girl-showing-ass-to-class-teacher_redband

Scene 1
Jesse Jane with Manuel Ferrara.



Scene 2
Memphis Monroe with Erik Everhard and Mick Blue.



Scene 3
Adrenalynn and Shawna Lenee with Johnny Sins.



Scene 4
Alexis Texas, Camryn Kiss and Shay Jordan with James Deen, Johnny Sins and Tommy Gunn.



Scene 5
Brianna Love and Stoya with Manuel Ferrara.



Scene 6
Adrenalynn, Brianna Love, Jesse Jane, Lexxi Tyler, Memphis Monroe, Priya Rai, Shay Jordan, Sophia Santi and Stoya.

That's Alexis Texas, if that helps anyone to find the vid.