Three times in the past three months, more than a thousand parents from north Fulton County have filed into the Alpharetta High School gymnasium anxious to see whether the latest redistricting map shows their children landing a good school assignment or being uprooted.

Some were pleased with what they saw. Others were upset. And still others were withholding judgment. One final map is due out in May before the school board settles on a final redistricting plan.

The latest proposal, revealed last week, doesn’t force Roswell High School freshman Tristan Kaisharis to change schools. But it has half of the members of his soccer and swim teams being shifted to rival Milton High School, said his mother, Jennifer Kaisharis.

“Most people may be happy, but the Roswell people aren’t,” she said.

School attendance boundaries can determine the quality of a child’s education, influence home values and create or break up cohesive neighborhoods. And their redrawing — which happens fairly frequently in metro Atlanta amid population changes — gets parents revved up.

In north Fulton, the uproar is over the redrawing of attendance zones for the fall 2012 opening of a new $66.8 million high school on Bethany Bend near the Forsyth County line.

Administrators initially planned to relocate students from seven high schools as it filled the new school. That’s since been scaled back to 2,169 students at four high schools — Roswell, Milton, Alpharetta and Johns Creek — with Milton and Roswell being the most impacted and upset, if e-mails, petitions and online comments are a gauge.

“Quite frankly, we believe Milton is being sacrificed,” said Milton resident Kathy Canouse.

Milton is currently set to lose 1,320 of its 2,626 students to the new school.

Roswell High would shift 481 of its 2,463 students to Milton, a move that Roswell Mayor and Roswell High alumni Jere Wood, among others, openly opposes.

Wood’s big objection: The plan doesn’t recognize the need to keep the city, which still has a small-town feel, and its schools together.

Jennifer Kaisharis said the city’s friendly atmosphere and its high-quality schools are what drew her to Roswell and are what she worries will be lost.

“Everybody just got a knife stabbed in our hearts,” she said.

Linda Schultz, school board president, knows some people want the new school districts to align with their cities.

“But we’re a county school system, and we have to look at how we can use our resources most effectively and efficiently for the whole county,” she said.

Residents of both Roswell and Milton say they are concerned that their schools’ test scores and reputations could be jeopardized because, under the current plan, each of the schools will lose some stable, engaged neighborhoods and be forced to pick up others.

Both schools have good academic track records.

The average SAT score for Roswell High students was 1671 in 2009, compared with the county average of 1584 and the state average of 1460. Milton’s average was 1657.

Kaisharis said Roswell residents are concerned their school will become “a dumping group.”

Gina Kellis, who lives in the Milton High school district, is a 1989 graduate of Fulton’s Riverwood High School. She said her alma mater lost its reputation as the system’s “crown jewel” after some “poor decisions” by the school board in the late 1980s and spent 20 years battling back.

“I hate to see decisions made that will make Milton fall from the top,” said Kellis.

Canouse and Kellis said the school board has carved out an elite area for the new high school, instead of having all of the school districts take a share of the more diverse areas.

“Diversity is good, and you can have that at all the schools and benefit them all,” Canouse said.

The board’s Schultz said she knows some people are unhappy.

“Some are angry. Some are OK,” she said. “We’ve had a lot of different emotions going on. This is a very difficult redistricting because it involves high school and potentially a lot of students.”

Some have complained that the proposed redistricting will compound traffic problems in north Fulton and make for much longer commutes for young drivers. School administrators insist they followed official criteria — geographic proximity, followed by school capacity and enrollment projections.

Mike Nyden, leader of an unofficial group of mostly Roswell residents against the redistricting plan, said last week he is receiving about 30 e-mails a day from people unhappy with it.

He said, “What I’ve seen is neighborhood against neighborhood, which troubles me, and a process that is horribly flawed and does not solicit real input.”