Prospective principals will have to pass a six-hour test of their administrative skills before they can take up a post in a clutch of American states.
The test will be conducted by the Council of Chief State School Officers and the Educational Testing Service, a private agency that also administers tests for students and teacher-trainees.
Proponents say it is only fair that school leaders should be subject to the same rigorous assessment as teachers and students.
The test will be given to prospective elementary and secondary school principals in Maryland, Mississippi, Missouri and North Carolina, beginning in the autumn.
Illinois, Kentucky and the District of Columbia also are expected to adopt the plan.
The Council of Chief State School Officers said it was necessary to be sure that school leaders will enact educational reforms.
"The school campus is the proving ground of the reforms states enact," said Gordon Ambach, the council's director.
"Either the changes happen or do not happen there, and we know that they are less likely to happen if a new principal is not prepared to lead."
As part of the test, candidates must answer questions about such tasks as handling a budget and evaluating staff, and how they would act in given situations.
Principals have not previously required licences, though in 35 states it is compulsory for prospective teachers take proficiency examinations.
Question "The students in an elementary school are practising for the annual holiday concert. A parent insists that her child not be required to sing any of the Christmas songs. The principal excuses the child from participation .
Do you agree with the principal's actions? Give a rationale, citing relevant factors.
Answer (The correct answer would cite civil and religious rights of the parent and student and include at least one of the following: meeting with the student and parent to discuss the objections; suggesting an alternative activity for the student; and examining the content of the concert to determine its appropriateness for all students.)