Two states—Nevada and Mississippi—will get extra time to implement the teacher-evaluation portion of their waivers from the No Child Left Behind Act, the U.S. Department of Education announced today. These are the first two states approved for the so-called “waiver waiver”, which allowed states to get an additional year to fully implement systems that gauge teacher performance using student outcomes.

So far, teacher evaluation has been the trickiest piece of the waivers, which have been granted to more than forty states and the District of Columbia. States were originally supposed to have those systems fully in place by 2015-16, although each state set a slightly different target date in their waiver request. But, in July, the department announced that states could ask to extend that deadline to the 2016-17.

For instance, Mississippi was originally supposed to have its teacher evaluation all ready to go by the 2014-15 school year, and will now be able to hold off until 2016-17. And Nevada’s educator evaluation system was supposed to be completely up and running by 2015-15. Now they also have until 2016-17.

Thirty-four waiver states were allowed to apply for the flexibility , and 12 said they were interested. Expect the Education Department to announce more “waivers waiver” decisions in coming weeks.