Thao "Sandy" Doan is a former a teacher at Raul Quintanilla Sr. Middle School.

She coached track and cross county at the school. ^[0]

On January 20, 2017, Thao was arrested on a sexual assault charge in Dallas, Texas after admitting she had a sexual relationship with a 14-year-old student. ^[0]She was taken into custody after the student's mother approached the school with screenshots of messages between her son and the teacher. ^[0]

The student had also blackmailed Thao out of $28,000 to keep their tryst a secret. ^[0]She told police that the two had corresponded via Instagram before having sex in a park in June 2015, and continued the affair throughout November and December. ^[0]