A teacher at a Tulsa charter school attended by the daughter of an unarmed black man killed by a white officer says the tragedy "lives and breathes" among her classmates in a moving essay she posted on Facebook detailing her experience helping students cope.

Rebecca Lee is a teacher at KIPP Tulsa College Preparatory. She writes that she facilitated three small-group discussions about Terence Crutcher's death. She says one group included sixth-grade classmates of Crutcher's daughter.

Lee writes that she's sharing her experience to give people "a clearer understanding of the crisis we're facing and why we say black lives matter."

Lee posted the essay Wednesday evening. It had been shared more than 135,000 times by Friday morning.

Tulsa officer Betty Shelby is charged with first-degree manslaughter in Crutcher's death.