Fairfax County School Board members on Thursday deferred an application to open the first public charter school in Northern Virginia, praising the aims of the school’s advocates but objecting to the proposed site.

Board member Sandy Evans emphasized at the Thursday night meeting that she and other members remain interested in the proposal for Fairfax Leadership Academy, which would cater to teens at risk of dropping out, but she said it was unclear to her whether the charter school could successfully target the county’s most troubled students.

“The proposal does still need some work, and this motion provides the time for that work to take place,” Evans said.

Supporters and opponents of the application said the deferral was expected after the proposed charter school failed to receive a $625,000 federal grant two weeks ago.

The chief sponsor of the proposal, J.E.B. Stuart High teacher Eric Welch, said his application for the U.S. Department of Education’s charter school implementation grant lost points because of “a chicken-and-egg problem”: He did not have school board approval.

Welch said the deferral gives supporters a chance to finesse the proposal’s details, especially those concerning funding. He said he hopes to present the school board with more information and gain its approval, then possibly apply for the grant again.

“Overall, we feel like this is a step in the right direction, even though it means more time,” Welch said.

Although the board plans to revisit the application, it rejected Fairfax Leadership Academy’s proposed site at the former Graham Road Elementary School. That location had rankled some parents at nearby Falls Church High School, who said the charter could suck students and resources from their school.

Falls Church High PTA member Joan Daly, who has opposed the charter, said taking the Graham Road Elementary site off the table is a step in the right direction.

On Wednesday, Daly had said she “really hadn’t heard . . . a justification for why the school needs to exist.” But she said Friday that if Welch and his allies ensure that the charter will serve the most at-risk students rather than siphoning off high achievers from public schools, she might support its creation.

“I think the mission is laudable,” Daly said. “It’s not an easy yes or no.”

Daly added that she is also concerned that the charter school will strain the school district’s budget.

That has also been a concern for district officials. They declined to endorse the school’s application in September, citing concerns about its finances. Deputy Superintendent Richard Moniuszko said the school’s proponents had indicated that the school would receive funding from the U.S. Education Department and local businesses, but had not provided the county with written commitments from those sources.

The Fairfax Leadership Academy proposal won unanimous approval from the state Board of Education in April. But under Virginia law, the county board has ultimate authority to approve or deny charter applications.

Welch said he and his allies will most likely spend the next three to six months looking for funding sources and finding a new location. Their success will determine when they come back to the school board.