About 19 percent of students at the city’s lowest-performing schools are required to attend summer school this year, compared to about 6 percent of students citywide, according to data released Thursday.

Among schools in the city’s “Renewal” improvement program, 1,865 students in grades 3-8 must take summer classes because they did not meet passing requirements. By contrast, 9,821 students in those schools were promoted to the next grade based on their classroom work and state test scores.

Citywide, the number of students sent to summer school continued to decline this year. That pattern began in 2014 under Mayor Bill de Blasio, who banned schools from sending students to summer school based solely or primarily on their test scores — a rule change that brought the city in line with a new state law.

This year, just over 18,300 elementary and middle-school students across the city must attend summer school, down from about 19,300 last year. In 2013, before the policy change, about 32,200 students were assigned to summer classes, or roughly 10 percent.

In August, schools review students’ work and assess whether it improved enough to meet promotion standards. Last year, 14 percent of summer-school students still did not reach that benchmark and were forced to repeat the same grade, according to the education department data.

Officials said the city has expanded summer-enrichment programs to serve an additional 12,000 students, including students at high schools in the Renewal program. This year’s $66 million suite of required and enrichment programs, dubbed “Summer in the City,” will also feature new teaching materials and visits to cultural institutions, the officials said.

“We’ve designed the new and expanded Summer in the City program to address the ‘summer slide’ head-on with rigorous, Common Core-aligned instruction to get kids prepared for September,” Chancellor Carmen Fariña said in a statement.