Starting this September, students in America's fifth-largest city - where 66 per cent of the 185,000 students are black - must finish the year-long course in order to complete their schooling.
Officials hope the curriculum changes, announced to parents last month, will engage inner-city students and offer a more representative view of history.
The course will promote students' "self-awareness and self-esteem" and addresses calls from the local community for history instruction to be more reflective of their heritage, said Sandra Dungee Glenn of Philadelphia's school reform committee, who proposed it.
It will span the history and cultures of Africa, enforced migration to the US during the slave trade and African American history through the civil rights movement and other pivotal episodes, to the present. It will redress "Euro-centric" approaches to history that have overlooked black experience and downplayed black contributions, she added.
Black studies is an established course in US universities. But Sam Wineburg, an education professor at Stanford university and an expert in school history instruction, said Philadelphia's move was "precedent-setting" among education authorities.
"It'll be interesting to see students encountering history where African Americans are in the centre of the narrative rather than being handmaidens," he added.
Blacks, who mainly live in cities, comprised 13.3 per cent of the US population in the 2003 census - narrowly overtaken by Hispanics as the largest minority. However, the initiative has aroused opposition from the speaker of Pennsylvania's House of Representatives, John Perzel, who represents a largely blue-collar white Philadelphia community in the state legislature, and last month complained to education chiefs.
A spokeswoman for the Republican law-maker said he welcomed the "teaching of African American history within a multi-pronged approach" but opposed "singling out one ethnic group", adding that the course was a distraction from academic basics.
Ms Glenn countered that it would make the curriculum more inclusive and boost academic performance by motivating and inspiring its 15 to 16-year-old students.