Arlington County Public Schools' efforts to prevent children who live within walking distance of their schools from riding the bus has left many county parents angry and confused.

The schools previously decided that students who live within a mile of their elementary school -- or a mile and a half from their secondary school -- are close enough to walk. However, school officials last year learned that many of those students who were supposed to walk to school often only walked to the nearest school bus stop and rode to school.

In response, school officials this year are issuing "vouchers" to students who are allowed to ride the bus. Students who live within walking distance and who don't have to cross a major highway to get to their school won't get vouchers and won't be able to board the buses.

School officials, who say the new restrictions are needed to make the bus service safer and more reliable, notified parents of the change in July. With school set to start Sept. 4, however, some students are still waiting for the letters telling them whether they're allowed to ride or will have to walk.

"Right now, I have no idea if my children are eligible to ride the bus," said Audrey Lesesne, vice president of internal relations for the Jamestown Elementary School Parent Teacher Association. She called the handling of the new restrictions "very unfortunate."

Still, Clarence Stukes, Arlington's assistant superintendent for facilities, said the changes are necessary. The bus routes are now more efficient and safer because school officials can be certain which students are riding the buses, he said.

It's not clear how much money the school system will save because of the changes, Acting Director of Transportation John Matthews said.

Arlington County parents should receive a letter notifying them of their child's status by next week at the latest, Matthews said. Parents may call 703-228-8670 with questions.