Marshalltown Schools Superintendent Marvin Wade said the school district will not make up the 14 hours of instructional time missed last week due to the heat.
The school district let out during the noon hour all five days last week due to the temperature.
"We are not required to make up the time - and the costs associated with doing it voluntarily would be significant," Wade said.
Costs would include transportation, food service and other costs that go into the day-to-day operation of the schools.
"The costs would be above what we normally pay for," Wade said.
Even though the hours do not need to be made up, Wade weighed whether it was worth the increased costs to bring students in to make up that time missed.
"Any time there's a loss of instructional time it is a concern," Wade said. "I hate to see it, but I've accepted the fact that we have the loss of instructional time."
Wade said last week he would consult with his fellow school superintendents and building principals before making a decision on the missed time.