With the threat of opt-outs looming, more than 400,000 city public- and charter-schools kids on Tuesday sat for the first day of the Common Core English Language Arts tests in grades 3 to 8.

While the number of kids pulled weren’t immediately available, data from nearby Westchester, Rockland and Putnam counties showed preliminary numbers on par with last year — with 20 percent of students across the state sitting it out.