Cardinal Roger Mahony announced last week that the archdiocese would become the first school system in California to move to a 200-day academic year. Mahoney said the idea was to improve student performance.
The change would have affected some 52,000 students in three counties.
But some parents complained that would disrupt family schedules.
On Tuesday, Chancellor Mary Elizabeth Galt said the decision on whether to add instructional days will be left up to the 210 elementary schools.
The Los Angeles Times says 15 schools already have the longer school year and 70 percent of the schools have said they will adopt it.
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