POST FALLS, Idaho — Ann Rosenbaum, a former military police officer in the Marines, does not shrink from a fight, having even survived a close encounter with a car bomb in Iraq. Her latest conflict is quite different: she is now a high school teacher, and she and many of her peers in Idaho are resisting a statewide plan that dictates how computers should be used in classrooms.

Last year, the state legislature overwhelmingly passed a law that requires all high school students to take some online classes to graduate, and that the students and their teachers be given laptops or tablets. The idea was to establish Idaho’s schools as a high-tech vanguard.

To help pay for these programs, the state may have to shift tens of millions of dollars away from salaries for teachers and administrators. And the plan envisions a fundamental change in the role of teachers, making them less a lecturer at the front of the room and more of a guide helping students through lessons delivered on computers.

This change is part of a broader shift that is creating tension — a tension that is especially visible in Idaho but is playing out across the country. Some teachers, even though they may embrace classroom technology, feel policy makers are thrusting computers into classrooms without their input or proper training. And some say they are opposed to shifting money to online classes and other teaching methods whose benefits remain unproved.