Jennifer Mulchandani learned this week that Arlington County Public Schools was splitting her neighborhood in two.

Mulchandani's children and some of the other Taylor Elementary School students living nearby rode a bus to school last year and will be allowed to do so again this fall. But other children in the same neighborhood are being banned from school buses this year. They'll have to walk to school from now on.

"It's just a slap in the face," said Mulchandani, one of several parents now lobbying the school system to abandon new rules that will force more children to walk to school.

"Arlington always talks about how it's moving towards public transportation and encourages us to use it," she said. "But now they're telling us we have to drive our kids to school and that we're not allowed on the public transportation."

School officials say they are trying to limit the number of students riding buses this year to cut costs.

Students who were supposed to be walking to school -- those living within a mile of their elementary school or a mile and a half from their secondary school -- were instead walking to the nearest bus stop and taking the bus, officials learned. To prevent that, students eligible to ride the bus are being given vouchers this year. Students who don't have vouchers won't be allowed to board.

But as parents learn this week whether their children will ride or walk when school opens Sept. 4, opposition to the changes began to grow. Parents started a Facebook group -- Arlington Parents for Safe School Transportation -- and launched an online petition to protest the changes.

"Our children were not illegally hopping on the bus to avoid walking to school," said Pam Girardo, who also learned that her children will have to walk to Taylor from now on.

"They were eligible last year, but not this year," Girardo said. "The school's [previous] walk-zone document clearly indicated that our neighborhood was well outside of the designated walk zone and had been that way for decades."

School officials said parents can appeal their child's designation, but Girardo said the letter offered no explanation for how to file an appeal.

Schools spokesman Frank Bellavia said each appeal will be heard on a case-by-case basis.