District superintendents say the new Smarter Balanced Assessment Consortium test will be costly and gobble up too much classroom and computer lab time.
If the exam takes eight hours or more to finish, "then we really ought to rethink that," Boise Superintendent Don Coberly says.
The state Education Department concedes that the new test will take more time, but says it also will yield more comprehensive data.
Putting the exam on hold "moves us backward," says Luci Willits, chief of staff to state Superintendent Tom Luna.
The two sides will meet on Dec. 20 to discuss their differences.
Significantly, this rift has nothing to do with the Idaho Core Standards themselves - new math and English language arts standards that are designed to encourage critical thinking and emphasize writing skills.
Idaho schools began teaching to the standards this school year. In April and May, all third- through 11th-grade students will take the exam. But this is, in essence, a test of the test; under a one-year federal waiver, the Idaho scores will not be used as a school-accountability measure.
The school districts also worry that the computer-based exam will take so much time, students won't be able to access lab computers for other assignments.
While the exam will take up hours of learning time, the superintendents don't expect to get student-level data that will help teachers. They're expecting to see little more than broad trends.
"I think (with) an eight-hour assessment, we ought to learn a lot about our kids," Emmett Superintendent Wayne Rush said Tuesday.
Willits said the overall cost will be comparable to the computer-based test being replaced. And the new test will be worth the extra time, because it will better measure critical-thinking skills.
Idaho's Education Department wants the test to be fully in place by the spring of 2015 and use the results for the next round of school five-star ratings.