Mount Vernon High in Fairfax County has standards far above most schools serving low-income areas.

Forty-six percent of its students come from families poor enough to qualify for federal lunch subsidies, yet, the school has become known for its demanding courses. Its International Baccalaureate program has kept it among the top 5 to 10 percent of U.S. high schools measured by participation in college-level tests.

Last year, however, the school slipped. There was a sharp drop in the number of students taking IB. Mount Vernon went from 493 IB exams in 2010 to 337 in 2011, a 32 percent drop. As a consequence, it will be the first Fairfax high school in a decade to fail to make my annual list of the most challenging high schools in the country, when The Washington Post’s High School Challenge rankings are published this year.

The drop is only temporary. IB enrollment at Mount Vernon has rebounded. But it is important to remember what happened last year. Even schools with great academic track records can falter when school boards and program coordinators fail to meet their responsibilities.

Mount Vernon was the subject of my 2005 book, “Supertest: How the International Baccalaureate Can Strengthen Our Schools,” about the rise of IB in the United States. One of the heroes of that story was Dan Coast, a science teacher who transferred to Mount Vernon from Charles County because he wanted to teach IB biology. He had been a star at his old school, but the demands of IB knocked him askew. He was devastated by feedback that he was not covering the syllabus and that his students had no understanding of vital organic processes.

He rose to the challenge and worked long hours to improve, as he had been telling his students to do. He became not only a successful IB teacher but the coordinator of Mount Vernon’s IB program.

Then he became a vice principal, and one of the IB coordinators who replaced him let him down. The coordinator took a leave in September 2008. Coast and Mount Vernon Principal Nardos King said they thought it would be a short absence, but the coordinator delayed her return until January. She failed to contact all the promising sophomores that year and persuade them to enroll in the full IB diploma program.

It takes effort to persuade teens to commit to a battery of courses, six long exams and a 4,000-word research paper. By last spring, because of the recruiting failure, Mount Vernon had half as many diploma candidates as usual.

A second blow came late in 2009 when the School Board, facing a deficit, said it would charge students $75 for every IB or Advanced Placement exam they took in spring 2011. The cost was too much for many students, who dropped IB courses they had planned to take that year. Mount Vernon students Eugene Coleman and Christalyn Solomon appeared at a board meeting to complain but were rebuffed.

Virginia Attorney General Ken Cuccinelli II (R) ruled a year later that the test fees were illegal. But it was too late to repair the damage to 2010-11 enrollment. Only if the School Board had checked the law or found some other way to pay the $37,000 in IB fees at Mount Vernon, or if the coordinator had returned sooner, could the year have been saved.

Maintaining a great school is a high-wire act. Even small missteps have consequences. But in this case, it was only children’s futures that were affected. It will take some time for people to notice.

To read previous columns by Jay Mathews, go to