If York history Professor Jerry Ginsburg were to apply for his job these days, he wouldn't be first choice. That's because he's a white man teaching black history. And that's despite pioneering African-American Studies at York University and winning two awards for teaching them.

Seventy per cent of the students in his introductory course are black. Eighty per cent are female. During the first class, Ginsburg breaks the ice: "Some of you may not have noticed this, but I'm not black." Then he analyzes the class dynamics. Minority white students may hesitate to express their opinions, he says, and black students may worry that speaking up will result in reprisal from a white prof. A class that's afraid to talk won't do.

In 1986, after 15 years of teaching American history, the Denver-born professor leapt at a chance to create a new introductory course. He and a colleague decided to focus on the evolution of Harlem (Evolution of Urban Black America, 1830-1930), covering everything from slavery to the growth of northern cities. Ginsburg is still teaching it along with a fourth-year course, Race and Politics in the U.S. since WW II.

Ginsburg found a staying power that has eluded other white scholars of black history in the United States. "A lot of it has to do with how you teach and your willingness to open up and allow students to criticize anonymously." Students can critique his class - and him - in monthly "reaction" papers they sign by number. Ginsburg reads the papers to the class. "I want them to see that it is possible to make a serious criticism that doesn't result in anger or retribution." Of the thousands he's received, only four have criticized him personally.

No subject is too uncomfortable. "I like to teach at the edge so people can see the relevance to their daily lives." The class discusses stereotypes, class hierarchies within black culture and colourism (valuing lighter skin), a legacy of slavery.