IN VIRGINIA, the shortage of math and science teachers is acute, because of the mushrooming of high-tech companies, which lure a huge proportion of those with a technical bent, and changes to the education degree requiring students to major in the subject that they will teach. Rather than ease that rule, though, the Virginia state education board this week took an opposite and, in many places, controversial tack: making it easier for people from other professions to become teachers later in life.

Alternative licensure has been hotly contested wherever it is proposed. Teachers' unions and schools of education hate it. Critics raise legitimate concerns about the need for safeguards when people who may have strong skills but no experience in applying them to children are steered directly into classrooms. One state, New Jersey, successfully has met those problems and, over 20 years, created a widely admired alternative certification route. New Jersey has no teacher shortage.

The Virginia proposal, given preliminary approval at a board meeting Thursday, has some points in common with this successful plan. It adds to the requirement for an undergraduate subject major an option for experience "equivalent to the degree" in a subject. Applicants would be required to pass the teacher exams that education graduates take; they would then take an intensive summer course on classroom skills. Schools that wished to hire them, through the regular hiring process, would give one-year provisional contracts and assign a mentor. Initially, the plan would be open only to military retirees -- a plentiful population in the state and one flush with engineers, navigators and others whose work experience can be judged substantially equivalent to an undergraduate degree in science or math.

The key here, as with most education policies, is alert supervision by individual principals, who must be ready to fire a provisional teacher who cannot make the transition to a classroom. Bringing in untested teachers with a richness of other experience can mean risk. Correctly handled, though, it is a risk with a big potential payoff.