More than 1 million public school students estimated to be affected by Hurricane Harvey

— -- As Harvey continues to bring devastation to the Gulf Coast, the Texas Education Agency estimates more than 1 million students in the state's public school system have been affected by the storm.

“Roughly 20 percent of our student population has been affected by Harvey,” Texas Education Agency spokeswoman Lauren Callahan told ABC News Wednesday. “This is absolutely an ongoing situation and our first and foremost priority is making sure everyone is safe.”

The TEA, which oversees the education of 5.3 million public school students, reports that 200 of the state’s 1,200 school districts have had some sort of closures this week.

Aransas County Independent School District, which includes schools in the hard-hit town of Rockport, announced Wednesday that schools in the district would be closed "indefinitely."

The district serves 3,316 students, according to its website. A later statement from Superintendent Joseph Patek to clarify how long schools will be closed painted a stark picture of the area's current conditions and road to recovery.

"We used this word because we are attempting to be as transparent as possible. We do not have a timeline for how long the recovery process will take," Patek's statement read. "We must first have drinkable water and power. After that, we must ensure our facilities are safe and then we will be able to allow teaching staff in the buildings to look at their needs for supplies."

Students in Houston, the state’s largest city, where an estimated 30,000 to 40,000 homes have been destroyed, were supposed to start school on Monday.

Today, on the eve of what would have been the end of the first week of school, district officials have only been able to reach around 45 of the district’s nearly 300 campuses to assess the damage.

“We’re anticipating once the waters start receding, we’re going to be finding pretty extensive damage,” Houston Independent School District (ISD) Superintendent Richard A. Carranza told ABC News Wednesday, adding that water and roof damages and power outages have been found so far in the accessible campuses.

Houston’s school district is the largest in the state and the seventh-largest in the U.S., and serves around 215,000 students and 29,000 employees, according to its website. Carranza said district officials assume 90 percent of students were affected by Harvey.

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The district announced today that schools will reopen on Sept. 11, conditions permitting.

Administrative staff will return to work next Tuesday, with teachers returning to their classrooms on Sept. 8.

Students will be allowed to follow a relaxed dress code policy through the end of the year, the district also announced.

The school district is working with the Council of the Great City Schools, a coalition of 68 of the nation’s largest urban public school systems, to place crisis counselors in schools when they reopen and make sure students have the clothes and school supplies they need, Carranza said. The district has already posted a resources page on its website for employees.

Houston ISD also announced Wednesday that all students will receive three free meals per day during the 2017 to 2018 school year through the National School Lunch/Breakfast Program in the wake of Harvey.

“Once [the students] come back we promise that we’re going to love them and they’re going to have a safe place to learn,” Carranza said, telling students and parents directly, “So just hang in there and we’re going to see you.”

The stability of the school day will be a crucial element for students and staff as school districts across Texas recover, according to Doug Harris, professor of economics at Tulane University and the director of the Education Research Alliance for New Orleans.

Harris studied the rebuilding of the New Orleans school system after Hurricane Katrina.

“One thing we saw in New Orleans that you can expect in Texas is, especially for young kids, it’s easy for them to be traumatized and have symptoms like post-traumatic stress disorder that are long-lasting in something like this,” he said. “One lesson just from that alone is that you want to get them resources.”

Harris continued, “Make sure [students] are being fed and have access to counselors and give them a sense of normalcy as quickly as possible.”

Kathryn Mills, a second-grade teacher in the Katy Independent School District, which has been closed since last Friday, is using social media to give students a sense of normalcy while they are still home from school.

Mills, a mother of two, created the Hurricane Harvey Book Club after seeing photos on Facebook of students gripping books as they sought shelter in bathrooms and kitchen pantries during near-constant tornado warnings in the Houston region.

“It was super heavy on my heart to try to find a way I could get their mind off of it,” said Mills, who invited a handful of Facebook friends to the group and asked them to post videos of themselves reading books for kids in Texas to watch.

The group has gone to 30,000 members in just a few days and Mills is receiving messages from publishing houses and authors who want to help.

“For me as a teacher, I’m watching these videos and I’m like, ‘That’s exactly what I wanted," said Mills. “One kid had to evacuate his house and went in and grabbed books because he wanted to be part of the book club.”

The Katy Independent School District, where Mills teaches, anticipates that schools will reopen next week for the district's nearly 90,000 students and staff members but officials are still trying to access some of the schools to see the damage.

“The safety of students traveling to and from our schools, along with ensuring the safety of campus building structures, is our number one priority as we consider the return date for students,” superintendent Lance Hindt told ABC News in a statement. "We will be updating the community on the status of school openings this week once crews have completed their assessments."

When students affected by Harvey are able to return to school, schools across Texas will be ready to welcome them.

“Our schools will certainly be able to take any student that is displaced because of the storm, for however long,” said the TEA’s Callahan who said the agency is working with their counterparts in Louisiana to implement best practices learned from Hurricane Katrina.

“We’re fully prepared to be of assistance to both our districts that have suffered unimaginable devastation as well as the districts who are taking in students because of the storm," she said. "Every district and charter in our state has a homeless liaison in the district in place already who can help get students enrolled."

Commissioner of Education Mike Morath announced this week that schools in the state's 58-county disaster declaration for Harvey can submit a waiver so they will not have to make up instructional days missed due to the storm.

One additional lesson from Hurricane Katrina, according to Harris, is that schools are a “natural point of connection” and parents should take their children to the school nearest their location, no matter where they have evacuated.

“The problem now is that not only are families living in different locations, if they’re not in a shelter they’re going to be disconnected and schools and social services won’t know that they’re there,” he said. “Schools are a great way to make that connection.”

He continued, “[Officials] should be getting the message out that kids should go to the nearby school even if it is temporary, and the state will have to step in with resources to make sure their needs are met.”