Last year, with fears about lead poisoning running high in the wake of the water crisis in Flint, Mich., New York City officials said that they had tested the water in all the city’s public schools and that the results should be reassuring: Only 1 percent of outlets had lead levels above the Environmental Protection Agency’s action level of 15 parts per billion.

But after The New York Times reported that the city had run the water in every outlet for two hours the night before taking the water samples, a process called flushing, experts said that the practice had most likely hidden lead problems. They said the city should throw out the results and redo the tests. In the end, the city did.

On Friday, the new results were released, and they paint a starkly different picture: This time, 8 percent of outlets had lead levels above 15 parts per billion. And the vast majority of school buildings — 83 percent — had at least one outlet with a lead level above the threshold. The city had previously said that two-thirds of its roughly 1,500 school buildings had no outlets above the 15 parts per billion threshold. Flushing cleans most soluble lead and lead particles out of the pipes and thus reduces lead levels temporarily.

Two schools in Queens were among the worst for the number of outlets involved.

At Public School 95, the Eastwood School, in Jamaica, which has 1,500 students, 34 outlets had lead levels above the E.P.A. threshold. A water fountain in the cafeteria had a level of 3,200 parts per billion. Several other water fountains — in the cafeteria, a play area and a school hallway — had lead levels more than 40 times the E.P.A. action level. When the school was tested the first time, under the protocol that included the flushing, the highest level found was 35 parts per billion.