DANVILLE (CBS SF) – School officials were responding Thursday to the discovery of racist graffiti found inside a boy’s restroom at Danville’s Monte Vista High School.

Students arriving for classes said they were shocked and disgusted by the discovery.

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The mother of an African American teen who discovered the graffiti said she’s worried about her children’s safety and well-being.

The bathroom was closed to students, the graffiti was cleaned up and Danville police and school administrators started an investigation to find the person or people responsible, San Ramon Valley Unified School District spokeswoman Elizabeth Graswich said.

The incident, however, has left LaLene Shepherd shaken and worried.

Shepherd’s son and daughter both attend the school and have been in the district since they were both 5 years old.

“You don’t want your kids in an environment like this,” Shepherd said. “It’s very worrisome.”

She said she and her family talked about the incident Wednesday after school.

“As the evening progressed, it became more and more worrisome,” Shepherd said. “I know that my kids are going to have to return to this place today.”

Two weeks ago, there were two incidents of racial graffiti at nearby California High School.

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In a letter sent to parents, San Ramon Valley Unified School District Superintendent Rock Schmitt said the graffiti the emotions stirred up in the current political environment.

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“In our District, harmful words used during the election coincided with two ugly incidents of racist graffiti at one of our high schools,” he wrote. “The words exchanged on the campaign trail and the racist words written on bathroom walls cry out for how much we need to support, teach and listen to our children.”

Schmitt wrote it was a critical time for educators to be leaders.

“As educators, it is our duty and calling to help young people navigate the world they live in, to teach students to think critically about the information whizzing around them, and to understand that our differences in opinion, taste, interest and culture make us stronger,” he said in the letter.

He said students must be made aware of the power of their words.

“It is important that our students understand that words matter. They can be very harmful, but also can make the world a better place when used thoughtfully and with respect for each individual,” he wrote. “This is not to say we have found the solution or that we are doing everything possible to combat harmful speech. While we have moved forward on the continuum, we still have a long way to go.”

The entire school faculty and all 2,400 students started Thursday at an assembly where teachers talked about their personal experiences with discrimination and 100 students got up to speak as well, according to Graswich.

“This is a difficult conversation to have but I think the school is doing a great job,” Graswich said. “I hope we can learn from this incident and create an environment where students can talk about these kinds of things and feel safe.”

Just 24 African American students, or about 1 percent of the total student population, attend Monte Vista.

Shepard says she’s hopeful that the district and school are taking the necessary steps to find whoever wrote the graffiti and to prevent future incidents.

“We’ll see what happens from this,” Shepherd said. “You hope for the best.”

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