The school is Santa Fe High School. From New York Post,

Breaking: Another school shooting, in Texas; 8 killed

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The school is Santa Fe High School.
From New York Post, May 18, 2018:

At least eight people were killed when a shooter opened fire on a high school near Houston on Friday, according to reports.
A law enforcement officer was also wounded in the gunfire, according to KHOU11 News.
The shooter, a male, has been arrested, according to the Houston Chronicle.

The school was placed on lockdown around 8 a.m. following reports of the active shooter on campus, according to assistant principal Cris Richardson.
One student told TV station KTRK that a gunman came into her first-period art class and started shooting. The student said she saw one girl with blood on her leg as the class evacuated the room.
“We thought it was a fire drill at first but really, the teacher said, ‘Start running,’” the student told the television station.
The student said she didn’t get a good look at the shooter because she was running away. She said students escaped through a door at the back of the classroom.

~Eowyn