MEXICO CITY — Mexico is mounting a final push to get all of the country’s 3 million school teachers vaccinated so it can reopen schools, perhaps by the second half of June.

President Andrés Manuel López Obrador said Tuesday that getting kids back into classrooms is an urgent necessity, as much for their social development as anything else. He says: “School is like a second home, and we need all students at all levels to return to in-person classes..”

Officials estimate 2.1 million teachers at private and public schools have already been vaccinated, and hope to inject almost 520,000 this week and a similar number in the last week of May.

Schools in four of Mexico’s least-affected states have gone back to in-person classes, but on a very limited scale. The other 28 states have been giving online classes since early last year.