LOS ANGELES (CBSLA.com/AP) — Officials with the Los Angeles Unified school district (LAUSD) are preparing for the possibility of a teachers strike amid an escalating rift over higher wages, smaller class sizes and evaluations.

Thousands of teachers demonstrated at a rally in downtown Los Angeles on Thursday as contract negotiations have stalled after more than six months of bargaining, and union leaders have declared an impasse.

While still several steps away, United Teachers Los Angeles President Alex Caputo-Pearl says teachers are prepared to strike if necessary.

Caputo-Pearl told KNX 1070 NEWSRADIO teachers are insisting that the district put its resources to better use.

“You can’t be in a district that has 3,000 classrooms with over 45 students in them,” he said. “You can’t be in a district that is 50th out of 50. California is 50th out of 50 in counselors among the states, and LAUSD is at the bottom of California.”

The union is demanding an 8.5 percent pay raise — a salary hike interim Superintendent Ramon Cortines says LAUSD cannot afford without instituting layoffs in “catastrophic numbers.”

LAUSD spokesman Tom Waldman told KNX 1070 the last time teachers went on strike in 1989 proved to be crippling for the district.

“I talk to former teachers who say that it was terrible on campus,” said Waldman. “You had teachers who walked the picket lines not speaking for years to teachers who didn’t walk the picket lines.

The last major urban district to experience a strike was Chicago Public Schools in 2012.

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