Over the summer, the mayor instigated a high-profile spat with the city’s charter schools after he suggested they are obsessed with test prep, and help inflate their scores by screening out English language learners and students with disabilities.

But at Wednesday’s rally, which organizers said attracted over 25,000 people, the rhetoric centered on celebrating the charter sector’s growth and encouraging more expansion.

“Today we celebrate surpassing 100,000 students in charter schools — 100,000 is not the top of the mountain!” Diaz said. And in a departure from the tone of his comments at last year’s rally, he added: “We don’t have to attack the traditional public school system. I support the traditional public school system, but I also support, 100 percent, charter schools.”