City schools keep losing kids.

Complaints about unsupervised children who went missing from school buildings, buses and field trips or were left unattended surged to 457 last year — nearly twice the 279 cases reported in 2014, the office of the Special Commissioner of Investigation for city schools told The Post.

The “disturbing trend” has gotten worse since SCI chief Richard Condon warned Chancellor Carmen Fariña in May 2015 that lax supervision was putting kids in harm’s way. Condon’s report came after the drowning death of Avonte Oquendo, a 14-year-old autistic student who ran out of his Queens school undetected in October 2013. His body washed up on a beach several months later.

The most alarming cases involve special-needs students and the city’s youngest charges, including 3- and 4-year-olds in pre-kindergarten, which Mayor de Blasio has made it his mission to expand.

At PS 154 in Queens, teacher Stephen Morganlander and substitute paraprofessional Jennifer Vasquez failed in July 2015 to supervise a pre-K boy who ran out of his gym class, left the building and walked four blocks home.

The school had no cameras and the doors had no alarms, SCI discovered. Last November, the city Department of Education claimed it installed more than 21,000 door alarms in 1,200 school buildings to prevent children from wandering off, as required by “Avonte’s Law,” passed by the City Council.

Click to read the story in the New York Post.