Boston Public Schools Superintendent Brenda Cassellius submitted her resignation on Monday to transition out of her role at the end of school year. "When I arrived in Boston in July 2019, I couldn’t have predicted that eight months later the world as we knew it would change. Since then we’ve confronted a global pandemic, reckoned with escalating racial division and civil unrest, and worked to repair community relationships that had eroded trust in our schools and confidence in our city," wrote Cassellius in her letter. "It is nothing short of remarkable that in the midst of it all we also developed a community-wide vision for equitable and excellent schools in every neighborhood of Boston; made historic steps forward in expanding access to our nation-leading exam schools; implemented a rigorous set of high graduation standards for every high school in the district with adoption of the MassCore; and put in place more just and transparent attendance, code of conduct, student privacy and grading policies." Cassellius thanked former Mayor Marty Walsh for hiring her, acting mayor Kim Kaney, and Wu in her letter.