On this site we’ve spent some time talking about the ways that Barack Obama has answered “sound bite” politics with “sound blasts” — 20, 30, or 40-minute-long videos of substantive speeches that defy our conception of the typical YouTube video (see Andrew Rasiej and Micah Sifry’s piece in the Politico for more).

The latest instance of this is very, very impressive. Today, to honor the 40th anniversary of the assassination of Martin Luther King Jr., the campaign sent out an email to supporters linking to the kind of unconventional campaign video we’ve come to expect from the campaign. (The video was produced by Obama's team.)

We meet Jackson Shafer, a white high-school teacher in the Bronx who’s been struggling to discuss the topic of race with his mostly non-white students. Referring to the flare-ups about race that inevitably occur at the school, Shafer says, “I think talking about it, I think addressing it, I think looking at it, is far more effective than pretending that it’s not there.”

Which naturally leads to… a clip from Barack Obama’s big race speech.

But after that, there’s no more Obama. Just Shafer’s students talking about how that speech, and Obama’s example, have helped them feel more involved in politics and have given them a deeper understanding of race in America. Obama’s videographers have captured some veritable breakthroughs.

But why now, why here? New York has already had it’s primary. Why not do this in an inner-city school in Philadelphia or Charlotte? That choice is just one of the idiosyncrasies that make this video different.

All three candidates tend to post slick videos presenting themselves as the ultimate leaders we can trust; it’s part of the game. But this video reads more like a snippet from a Jonathan Kozol book than a piece of campaign propaganda (though it is certainly that too). Having myself produced a video project about education in the Bronx, I recognized a lot in this piece; encouraging these students to think outside their frustrating day-to-day realities is no easy task.

Whether or not Barack Obama can be responsible for getting these students to transcend race and class is beyond me. But what is impressive is the way his campaign is willing to move beyond clichéd images of a grinning, affable candidate to a real, sustained look at how issues of race and class affect regular people. That this is a campaign video astounds me. No other campaign is doing anything like it. And it’s especially poignant on a day like this, when John McCain is getting major pushback about his past opposition to a national MLK holiday.

UPDATE: The NYC Education Department says the video violates department regulations forbidding filming in school buildings for promotional or political purposes. The department might bring disciplinary action against school, the Bronx High School for Performance and Stagecraft.