LOS ANGELES (AP) — The Roman Catholic Archdiocese of Los Angeles is adding 20 days to the academic year at its 210 elementary schools.

Cardinal Roger Mahony told a press conference Thursday that the three-county archdiocese is moving to a 200-day school year because of a clear relationship between substantive time in an academic setting and increased student performance.

READ MORE: Orange County Deputies Open Fire Inside Foothill Ranch Walmart, Suspect Wounded

The archdiocese says its school system is the first in California — public or private — to add 20 days. The federal mandate is 180 days.

READ MORE: Russell Westbrook Benched In Final Minutes Of Lakers Loss To Pacers

Kevin Baxter, superintendent of the elementary schools, says the goal is to have as many campuses as possible adopt the new calendar for the 2011-2012 school year. He notes the move will result in slightly higher teacher salaries and tuition costs.

MORE NEWS: Long Beach Unified's Classified Workers Threaten Strike After Contract Talks Break Down

(© Copyright 2010 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)