The ghosts of Mississippi do not haunt Bob Moses, but they are there. Sitting in Mr. Moses's class here at Lanier High School is Larry King, whose grandfather, R.L.T. Smith, was an African-American candidate for Congress in 1962. Mr. Smith got scarcely a handful of votes, though Mr. Moses logged many miles driving him around the Third District, knocking on doors.

 A few years back a girl named Lazazel turned up in Mr. Moses's math lab at the Brinkley Middle School and somehow seemed familiar. Sure enough, her grandmother ran the Wide Area Telephone System for the Mississippi Freedom Democratic Party, the integrated group that changed the nation's politics with its challenge at the Democratic Convention in 1964.

 Mr. Moses, who was among the first civil rights workers to penetrate Mississippi, has also reconnected with C.C. Bryant, the man who put him up in McComb County back in the day. A bus driver whose wife was in the movement, too, acts like long-lost kin.

And when he got a speeding ticket recently in Belzoni, a Delta town of 2,500, Mr. Moses paid the fine at the county courthouse where he had led so many black people up the steps to register to vote, only to end up face down on the concrete, beaten bloody by white onlookers or police officers. This time, the revolution Mr. Moses is running is much quieter. This time, he has managed to stay out of jail.

"This was the only venue where we could make the notion of civil rights stick," Mr. Moses, 65, said to explain what brought him back to Mississippi as a teacher 30 years after he left as
an organizer with the Student Nonviolent Coordinating Committee. "To make sense
of why we're here, you have to talk about the history."

An Equation for Equality

If Chapter 1 of Mr. Moses's Mississippi odyssey was about voting, Chapter 2 is about algebra.
They merge in his new book, "Radical Equations" (Beacon Press), expected in bookstores Feb. 1. The themes - equality, empowerment, citizenship - ripple through like ribbons, tying the two
experiences in the same long-term struggle. As the sharecroppers of a generation ago were "living in serfdom on plantations," Mr. Moses writes, "we are growing similar serf-like communities within our cities today."

"The political process has been opened - there are no formal barriers to voting, for example - but economic access, taking advantage of new technologies and economic opportunity, demands as
much effort as political struggle required in the 1960's," Mr. Moses says in the memoir, which was written with Charles E. Cobb, a journalist. 

"In today's world, economic access and full citizenship depend crucially on math and science literacy," he continues. "I believe that solving the problem requires exactly the kind of
community organizing that changed the South in the 1960's."

And so, every Monday, Mr. Moses leaves his home in Cambridge, Mass., to catch a 5:30 p.m. flight through Cincinnati to Jackson - a trip that can easily take more than seven hours of flying and waiting, waiting and flying - where he spends four days a week teaching high school math. As always, he is both foot soldier and leader. This time, the movement is called the Algebra
Project, which began 20 years ago when Mr. Moses would work problems with his children in his own home, and now serves 10,000 students in 28 cities nationwide. Based in Cambridge, it is a
nonprofit organization with an annual budget of $2.5 million.

 The notion is simple: Every child must master algebra, preferably by eighth grade, for algebra is the gateway to the college-prep curriculum, which in turn is the path to higher education, which is seen as the key to even basic success in modern society.

Mr. Moses has developed an innovative approach to mathematics to appeal to poor minority children, and to accommodate a variety of learning styles. But the Algebra Project is as much
about demanding rigorous education in low-income communities, where children are typically tracked into remedial classes, as it is about a particular teaching method.

 "It's the issue of the floor: How are you going to raise the floor?" Mr. Moses explained between classes at Lanier one day. "This work is really a much larger deal, this issue of really changing the culture of the community around the education of its children."

 Freeman A. Hrabowski III, a black mathematician who is president of the University of Maryland, Baltimore County, called the Algebra Project "an excellent way of connecting mathematics to
life itself" and "helping young people and adults understand that math is throughout life."

"Just as civil rights leaders helped people to understand how voting could transform lives and a community," said Mr. Hrabowski, who at age 12 marched with the Rev. Dr. Martin Luther King Jr. in
Birmingham, "Bob Moses's project is supporting teachers as they work to help children understand that learning algebra can help transform their lives."

An evaluation of the program by researchers at Lesley College, based in Cambridge, found that 92 percent of Algebra Project graduates in Cambridge enrolled in upper-level math courses in ninth grade - twice the rate of their peers in the city. At the M.L. King Academic Middle School in San Francisco,  which uses the Moses technique, 56 percent of black 1997 graduates took college-prep courses in the ninth grade, compared with 24 percent of a demographically similar group in the district.

Here in Mississippi, eighth-grade algebra students at the Brinkley Middle School scored 286.8 on the state's algebra test - slightly above the district mean of 284.9, for students in grades 8 through 12. Algebra Project students in West Tallahatchie, one of the state's poorest communities, scored 300.6, and those who attended a special workshop on graphing calculators scored 315.9.

The project has been most successful in communities with a homogeneous population that feels ill-served by the public schools; in places where minority groups compete, the organizing strategies are less effective.

 "What he did was directly tackle the problem of demand, have the students understand that systems have prevented their access to mathematics, and have them demand algebra from school
boards that have denied it to them," said Phillip Uri Treisman, a calculus professor at the University of Texas who is a national leader in efforts to improve minority students' performance in math and science. "He humanizes discussions in extremely practical ways. I have never seen anybody speak with such a balance of heart and mind as Bob Moses."

From Harlem to Hamilton

Before he became a civil rights worker, Robert ParrisMoses was a math teacher. For Mr. Moses, a devotee of the yogi Paramahansa Yogananda, math literacy, as he calls it, is almost a religion.

Raised in the Harlem River housing project, Mr. Moses attended Stuyvesant High School, the New York math powerhouse, then Hamilton College in Clinton, N.Y., where he played basketball and majored in philosophy and French. He was teaching math at Horace Mann, a private school in the Riverdale section of the Bronx, when the nascent sit-in movement drew him south in 1960.

Mr. Moses went to Mississippi, where no one had yet tried to organize the poor, illiterate, rural population, and quickly became a legend, his soft-spoken determination gathering legions of local
followers. He agitated in the state full time from 1961 to 1966, registering thousands of voters and training a generation of organizers in makeshift freedom schools.

 With his trademark denim overalls and strong moral leadership, he has been the hero of many books on the civil rights movement, and the inspiration for the movie "Freedom Song," which
was released recently on TNT.

Fleeing the Vietnam-era draft, Mr. Moses and his wife, Janet, moved to Tanzania, where three of their four children were born. After eight years teaching in Africa, he returned to Cambridge to finish his Ph.D. in the philosophy of mathematics at Harvard.

When his eldest child, Maisha, entered the eighth grade in 1982, Mr. Moses was frustrated that her school did not offer algebra, so he asked the teacher to let her sit by herself in class and do more advanced work. 

The teacher invited Mr. Moses - who had just received a MacArthur "genius" grant - to teach Maisha and several advanced classmates. The Algebra Project was born.

At its core, the project is a five-step philosophy of teaching that can be applied to any concept: Physical experience. Pictorial representation. People talk (explain it in your own
words). Feature talk (put it into proper English). Symbolic representation. 

One of the basic tenets is to teach integers by taking students on a trip - in Cambridge, on the subway; in the South, a tour of civil rights landmarks; elsewhere, a drive around the neighborhood or even a stroll around school. The children then draw what they saw, talk about it, write about it and eventually create number lines, then practice adding and subtracting positive and negative numbers.

Mr. Moses has also developed a set of manipulatives and math games, the crux of which is a version of craps using a three-dimensional model of monomials, binomials and trinomials.
Students roll dice of red, yellow and blue. Their scores translate into equations and, eventually, they calculate the probability of a WOFT - win on the first try. A separate curriculum teaches ratios through African drumming.

 "You can actually see what you're talking about, instead of just thinking about it in your head," said Tiffany Edmonston, 16, a sophomore at Murrah High School here in Jackson.

"I was taught to think," agreed Chris Adagbonyi, 18, a Murrah senior. "It taught me to use outside things to solve my problems."

The main reason Mr. Moses is teaching in Jackson - he and his assistants are paid by the Algebra Project, not the district, but students are randomly assigned to his classes - is to help him
create curriculum models.

"To develop mathematical materials, what you need is access to students, and you need access to the students you're trying to serve," he explained. When university professors far removed from
the laboratory of the classroom are doing education research, he added, "there's a gap between how they see things and what's going on in the minds of the students."

Students Teaching Each Other

At Lanier High, in a neighborhood of boarded-up homes and rusted-out cars, Mr. Moses's perch is in a dark corner of the first floor, a messy set of vandalized tables and folding chairs with
ripped cushions adjacent to a messier office and kitchen, the whole place feeling more campaign office than classroom. He presides here much like he did at S.N.C.C. meetings in the 1960's:
softly, often sitting down, pushing students to teach each other rather than follow him, the outsider.

He starts each morning upstairs in a pristine distance learning laboratory, teaching a class via satellite at Simmons High School in the Delta town of Hollandale. Mr. Moses waits awkwardly at the lectern, watching on TV screens as the students amble in and sling backpacks on desks, the universal sign of, I dare you to teach me something.

He tries, oh how he tries, but class keeps getting interrupted by loudspeaker announcements at both schools. Simmons has yet to find graph paper for the students. Mr. Moses can hear them
only when they turn on their microphones; he cannot see them clearly enough to tell when eyes begin to glaze.

 "James, you still there?" he asks hopefully. "Who's up there?" he says a few minutes later. "Tell us your name, and tell us why."

 Blindly, from Simmons: "Mr. Moses, are you asking a question?"

Soon, Mr. Moses plans to make the 100-mile trek to Hollandale, near Greenville, two afternoons a week to teach the class in person. But several of the Simmons students may drop out rather
than do math after school.

 Downstairs at Lanier, Alan and Michelle Shaw are guest-teaching Mr. Moses's classes. The Shaws, who met at Harvard, where they were tutors in the first Algebra Project school, now run the
organization's Web site; once a year, they come to Jackson with their three sons to teach computer programming.

The two oldest boys, 8-year-old Chinua and Yesuto, 6, stand in the middle of the room, following their father's directions to take four steps, turn 120 degrees to the left, and repeat three times, making an equilateral triangle. The high-schoolers, divided into groups around five computers, program them to do the same, and then to draw a set of 10 hexagons rotated 36 degrees each.

Meanwhile, across town, the gospel spreads. Twenty-eight Jackson teachers, among the 300 the Algebra Project has trained nationwide, are in a day-long workshop to follow up on a three-week institute they attended in the summer.

Elementary school teachers are sharing stories from their field trips to Medgar Evers's home and the library and monument to his martyrdom. Middle-school teachers are poring over interconnected
plastic blocks, trying to come up with new ways to teach three-fourths times one-third Even if students have dealt with fractions in elementary school, the Algebra Project philosophy
involves reteaching, getting students to think about math deeply, rather than just learning by rote.

One teacher sees three-fourths as three green blocks on top of a red, while another makes it a long stick with three red and four green. Interpreting the problem as, "What is three-fourths of
one-third, two separate groups take the 12 blocks, divide them into three groups (four blocks each), then take three-fourths of that to find the answer (three blocks, or one-fourth the
total).

 "I'm reaching students that I don't think I reached last year - the thug or the troublemaker or the kid who gets bored easily," said John Bakelaar, who teaches sixth and seventh grades at the
Peeples Middle School.

 Terrance, a former student, recently called Mr. Bakelaar to say he was having trouble with integers. Over Thanksgiving break, the two did a number-line trip, from the local sports museum
through the medical center, the mall, Burger King, a golf course, a baseball field and Swensen's ice cream shop. Terrance got a 94 on his test the next week.

"I was frustrated after last year - I thought I taught my butt off and I got results that were  terrible," said Mr. Bakelaar,who attended the Algebra Project workshop in the summer of 2000. "Now, I'm more effective, I'm having more fun, I'm not having the discipline problems."

The Young People's Project

 Math is the Moses family business.

 Maisha, the girl who inspired this movement, spent several years training Algebra Project
teachers after graduating from Harvard. Now 30, she is in Jackson, teaching her father's classes on Mondays, and helping older students tutor younger ones in the math games. Omowale, 28, is
spearheading the Young People's Project, an echo of the civil rights movement in which 150 teenagers act as "math literacy workers," singing the prime number rap and helping run
camps and workshops. Tabasuri, 26, is a rap singer who often works with the students; Malaika, 24, is in business school at Babson College, and last summer worked on getting patents for her father's math games.

The Moses children remember seeing books of lynching photographs when they were younger, though the memory has faded of their first trip South, by train for the 1982 funeral of Amzie
Moore, who had been chairman of the N.A.A.C.P. in Cleveland, Miss. Since the Southern Initiative of the Algebra Project began in 1991, they have returned to Jackson, one by one.

"I remember flying down here with my brother and wanting to see what was in those pictures," Omo Moses said. "I feel connected to what happened here."

In Jackson, Mr. Moses lives with Maisha, Omo, Taba and some of their friends, in what feels like a movement house in a sparsely populated area 20 miles outside of town. The Young People's Project offices are in the house, as is the studio for Taba's record label, Port Life; stray students often sprawl in the spacious living room, one typically camping overnight on the cot in what would be the dining room.

 The elder Mr. Moses, his head balding and his trim goatee gone gray, stays in the front room, where a yoga mat takes up much of the floor. A vegetarian for a quarter century, Mr. Moses rises before dawn to swim 1,000 yards at a gym, then goes back to the pool after school for another 1,000, gulping half-gallons of orange juice in between.

Memories of Mississippi, the Mississippi of the 1960's, are never far away. Over vegetable tempura in a trendy Japanese restaurant in Jackson recently, he cringed at the suggestion that
the National Guard might have gotten custody of the disputed Florida ballots, that it could be a fair institution. Back when the Algebra Project began at Brinkley, he was suspicious of a junior
F.B.I. club that started soon after.

And, always, he is motivated by the spirit of Ella Baker, that mother of the student movement, whose words about radicalism open Mr. Moses's book.

"The emphasis was on you, you have to do it, this is your job - that's the sense in which the vote was radical," he said. 

 Similarly, the Algebra Project is more about the students than the teachers, each one teaching one. "The legacy that's important is the organizing," he said, looking at his own children,
"the passing on."