Two teachers, Ann Perkins and Cynthia Tisdale, were among the 10 who died in Friday's attack.
Perkins and Tisdale were killed protecting children.
Perkins was in the art class where the alleged shooter opened fire. Santa Fe High School freshman Courtney Marshall was with her.
She said she hid in a closet with student Christian Riley Garcia as the gunman came into the room. Marshall says Garcia held the closet door closed. That's when he and Perkins were shot and killed.
"I was trying to tell him to get away from the door because I knew he was going to shoot at the door sooner or later," Marshall recalled. "I couldn't hear, really. Ms. Perkins was crying and screaming. She was very scared."
Ann Perkins - Teacher victim of Santa Fe High School mass shooting
Emergency dispatchers are also now sharing what it was like receiving 911 calls from teachers and teenagers as they begged for help.
"Pure chaos. 911 was ringing off the hook. There were about 20 calls on hold. I just sat down and started taking calls," said dispatcher Amanda Trevillion.
Trevillion, who is also a parent, told ABC13 talking to worried families was heartbreaking.
"Your heart bleeds not knowing where your child was. I think that was the hardest part, telling them we didn't have any information for them," she said.
Police don't know how many 911 calls were answered. Dispatchers from surrounding towns drove in to help with Santa Fe.
Cynthia Tisdale: Substitute teacher killed during Santa Fe High School mass shooting
There is still a teacher in the hospital. Flo Rice was taken to UTMB after being shot in the leg. She is in good condition.
The district also announced that anyone who needs to pick up their personal belongings from the school can do so Wednesday from 10 a.m. - noon.
Parking is available in the front visitor lot by the library.
Students in band or choir will receive information from their directors regarding when they'll be able to retrieve their personal items.
No cell phones or cameras will be allowed in the school.
Personal Items Pickup Information For Today, Wednesday, May 23, 2018https://t.co/MBgDBgiybi— Santa Fe ISD (@SantaFeISD) May 23, 2018
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