Dennis Walcott made changes to the city public school field trip policy Thursday, nearly a year after a student's death.
Former Columbia Secondary School teacher Erin Bailey will not face criminal charges in the 12-year-old's death.
Nicole Suriel drowned during a poorly-supervised school field trip to Long Beach in June.
Assistant principal Andrew Stillman chose an unguarded beach for a school trip, at which Nicole Suriel drowned.
Teachers at Columbia Secondary School are angry at the punishment given to the school's principal after a student drowned.
The teacher who let kids she knew couldn't swim into the water, leading to a girl's drowning, was fired.
Police have launched a crime probe after claims 12-year-old Nicole Suriel was allowed in the water.
Friday would have been the last day of sixth grade for Nicole Suriel, who drowned during a school trip this week.
Borough president Scott Stringer also called for all school trips to be halted as the city investigates Nicole Suriel's drowning.
Many stopped to pay their respects to Nicole Suriel at informal memorial outside the Columbia Secondary School in Harlem.