According to a Facebook note from the district, the tests were administered after the students became sick during music rehearsal.
However, the air was declared safe after the tests.
More information from the school district:
We want to inform you that we had three 3rd grade students fall ill this morning during their music rehearsal in the gym. Their parents were notified and protocols were followed. With the assistance of the KCK Fire Department and ambulance, the students were attended to and additional CO2 and gas leak testing was administered to be assured of air quality. There were no issues to report. We are in the process of checking the gas levels and are following the procedures set by the fire department. Your child's safety is our number one priority.
Safety measures and procedures were followed as a precautionary. All The air was tested and everything is clear. All the students are back in their classrooms and students are eating their lunches. The 3rd grade music program will go on!