But for tuition-free public school attendance, state law requires students to live in the district — a rule that many officials don't rigidly enforce. Some are uncomfortable with following the letter of the law because doing so could deny U.S. citizen children access to public schools. Also, turning away students cost the districts money.
Texas schools get funding for each student. Statewide, it works out to about $9,400 per student, primarily from local property taxes and state supplements designed to balance rich and poor school districts. Additional grants from the federal government for low-income and special education students account for about $920 per student. Cooper estimates his district of 10,000 students would lose $2.7 million if 400 students were expelled.
At the start of this school year, Cooper's district asked that Border Patrol agents count students crossing the bridge one weekday. Agency spokesman Rick Pauza said 550 students crossed, about 150 of them had student visas. The rest, Cooper said, are probably attending one of his schools.
School officials staking out the bridge handed out letters that warned parents they would be required to show proof they lived in the district. Within a few days, most parents offered documentation, meaning their children won't be expelled.
Cesar Casillas, who was picking up his 9-year-old nephew at Lamar Elementary School last week, said some parents were scrambling to find apartments in Del Rio, about 130 miles west of San Antonio. He disagrees with what the district is doing.
"These kids have all the rights to an American school," said Casillas, a 49-year-old who grew up in Del Rio.
It's a common argument, though legally, it has little weight.
"Citizenship doesn't give you the right to attend school. Residency does," said Elena Castro, assistant superintendent at California's Calexico Unified School District.