We met several students who said they did not go to school Monday because of what they believe are lingering symptoms from Friday night. In addition, some of their friends, they say, went back to emergency rooms over the weekend.
At Barnett Stadium in southeast Houston on Friday night, nearly two dozen students from Austin High School's dance team and band fell ill and were taken by ambulance to emergency rooms. For some, the diagnosis was carbon monoxide exposure.
On Monday at Barnett Stadium came the start of an investigation into how it happened. No portable generators at the stadium, the district says. For some of the students who were treated at ERs on Friday, Monday was a sick day.
"(Her hand) is trembling and they keep telling us that it's normal; it's normal, for the carbon monoxide," said the parent of one student.
There is concern about how the students became ill, but there is also concern over how the district handled the incident among some parents -- notification, for one.
"Because there were a lot of parents out there that they just, they didn't know anything. They were just scared our of their minds," said parent Mary Banda.
HISD Superintendent Dr. Terry Grier maintains HISD's emergency plan functioned as intended.
"We followed our procedure protocol; we got the kids to the hospital, we got them taken care of, parents were notified. It was handled right. The baffling piece is what was it," said Dr. Grier.
But some parents maintain they're equally baffled by the confusion and the ongoing medical complaints from their children.
Dr. Grier says he was notified in email of the incident just after 10:00pm Friday, but he didn't learn of it because his cell phone battery was dead. He says he learned of it on Saturday morning.
HISD has begun its forensic exam of the cause. They said city epidemiologists will interview students and school officials to get info on the whereabouts of the band members within Barnett Stadium and collect other health related-factors that could have played a role in the event. The district also said it has contracted for the services of Building Air Quality, Inc. to evaluate drainage systems, mechanical rooms, plumbing and electrical systems at the stadium.
HISD says its athletics department will determine whether the two UIL football playoff games slated to take place at Barnett this week will remain there or be moved, by Wednesday morning.
Stay with Eyewitness News and abc13.com for the latest on this story.