Calvin Lockridge in 1998. (Susan Biddle/The Washington Post)

R. Calvin Lockridge called himself a “race man,” a warrior for black children, a political maverick who was as proud of his Chicago street tactics as he was of his three master’s degrees.

Starting in 1978, he spent 12 years on the D.C. school board and nearly four decades in the hurly-burly of District politics. He cut a tempestuous path, throttling a fellow board member by the neck and proposing to shut down most of the city’s predominantly white schools. He also shared his family’s home with neglected children and railed against the inadequacies of a failing school system.

In 1993, he was convicted of stealing $20,000 from a 92-year-old retired school teacher who had turned her financial affairs over to him.

Mr. Lockridge, who died April 22 at age 81 at a rehabilitative center in Bethesda, Md., fancied himself a politically incorrect truth teller in a city he viewed as deeply corrupt. He was a go-to source for generations of news reporters, always eager to share documents from the towering piles of papers he collected showing what he saw as wayward spending by an out-of-control bureaucracy.

He was the rare elected official who laced even his public language with four-letter words, wore a gold earring and jeans to work, and littered the political battlefield with brash and bold accusations against his colleagues.

Years before then-Mayor Marion Barry was arrested for smoking crack in a downtown hotel room, Mr. Lockridge publicly called him a habitual cocaine user. Mr. Lockridge, who represented Barry’s home ward, Ward 8, on the school board, considered the four-term mayor a hustler and a phony, and Mr. Lockridge was field director of former Carter administration Cabinet member Patricia Roberts Harris’s failed 1982 campaign against the mayor.

Mr. Lockridge’s sharp tongue struck fear into some of his colleagues on the school board, especially in 1980, when he served a one-year term as president. The Washington Post editorial page called him “public nuisance number one” and said the board he ran was “a bad joke” that wasted its time on “vulgar tirades, physical intimidation and verbal harassment.”

But Mr. Lockridge saw his behavior rather as that of an irascible maverick who would do anything it took to reduce unemployment and improve education in his chronically impoverished ward.

“I am an emotional, explosive person,” Mr. Lockridge told The Post in 1988. “I walk with a certain amount of arrogance. I can be gentle and human, but I can also be loud, boisterous and intimidating. But understand this, brother. I live for nothing but improving the schools and educating black children.”

Many of the controversies surrounding Mr. Lockridge boiled down to disagreement over the role of the school board. Most board members said the superintendent should choose school principals and staffs, but Mr. Lockridge saw it as his role to funnel jobs to Ward 8 residents who otherwise found it nearly impossible to get work.

“I do plead guilty to ‘meddling’ in school affairs,” Mr. Lockridge wrote in a memo to Ward 8 school administrators in 1988, after an accrediting agency limited Ballou High School’s academic certification because of what it called Mr. Lockridge’s “interference” in school management. Two former principals said he pressured them to hire, promote and demote staff members ranging from administrators to janitors.

“I plead guilty to hustling jobs for the Ward 8 constituents,” he said that year. “I have made no bones about the fact that my constituents are generally not qualified for professional jobs. So when opportunities for custodians, food services and other jobs become available, I demand that those positions be made available to my constituents.”

He tended to view the school system’s shortcomings primarily through the prism of race. He led the fight against establishing the city’s first selective “academic” high school, arguing that such a school would be elitist and populated primarily by white students. (The school, Benjamin Banneker Academic High School, was approved; it opened in 1981 and its student population has always been well over 80 percent African American.)

Mr. Lockridge’s proposal in 1981 to improve the education of black children by closing most of the public schools west of Rock Creek Park — then the only part of the city where the population was majority white — was rejected by most school board members as blatantly racist.

For decades, Mr. Lockridge advocated the notion that white power brokers in the District were behind “The Plan,” a drive to restore the city’s majority white population and white political control.

“First you’re going to hear all about how the blacks who run the city are just too incompetent,” he said in 1987. “Then Congress is going to have to take over the police to keep the unruly blacks in line. Then they’re going to take over the agencies, one by one. You watch — this home rule mistake ain’t going to be around for long. The real estate boys won’t allow it.”

In 1997, on the day when the White House and Congress agreed to strip Barry of much of his mayoral authority and deliver extraordinary powers to an unelected financial control board, Mr. Lockridge declared himself prescient. “I’ve always said there’s a whole group behind the scenes — the business world, the Republicans, the Board of Trade — with a Plan to take it back,” he told this reporter.

Mr. Lockridge’s critics at times accused him of physical intimidation and the same kind of corruption that he so often railed against. In 1979, a fellow school board member asked police to arrest Mr. Lockridge for choking him during a closed-door board meeting. Police made no arrest. And in 1990, Mr. Lockridge was arrested after he punched the president of the D.C. Teachers Credit Union in the face.

Mr. Lockridge was convicted of theft and tax violations after he kept more than $20,000 that a retired teacher, Mamie Lee, had entrusted him with when she entered a nursing home. Lee had once employed Mr. Lockridge’s mother-in-law as a housekeeper. Mr. Lockridge spent 10 months in prison following that conviction in 1993.

Rufus Calvin Lockridge was born on a small farm in Columbia, Tenn., on Oct. 13, 1934. He worked on a tobacco farm to raise money to attend Morehouse College, a historically black college in Atlanta. He graduated in 1956, then joined the Army.

He later worked on the docks in Tampa and as a salesman for pharmaceutical and marketing companies before becoming active in the civil rights movement in Chicago in the 1960s. He ran the Black Consortium activist group there and twice lost campaigns for city alderman before settling in Washington in 1973 to run a school reading and math program in the Anacostia neighborhood.

In 1976, Mr. Lockridge earned master’s degrees in education and labor education from Federal City College, a predecessor of the University of the District of Colombia. Three years later, he received a master’s degree in political science from Atlanta University.

Mr. Lockridge — who died of congestive heart failure, according to his great-nephew and godson, Howard Miller — is survived by his wife of 38 years, the former Mildred Jones, who worked for many years as a school principal in Alexandria, Va., and six siblings. Mr. Lockridge had no children; he and his wife often took in troubled neighborhood children for extended periods.