That’s Mike DeGraba, a.k.a. the “Math Dude.” He is the star of series of short programs that provide instruction for Algebra 1. The shows air on Montgomery County (Maryland) Public Schools’s MCPS-TV, but all shows are archived on and downloadable from The Math Dude website. http://www.montgomeryschoolsmd.org/departments/itv/mathdude/
Each engaging video is 5-7 minutes long and utilizes real-world situations to teach Algebra concepts. Although the series is created for high school mathematics, many of the topics, such as absolute value, solving one-step equations and slope of a line, are suitable for middle grades mathematics classes.
You can follow Mike on Twitter (@the_math_dude).