By Mike DeNardo

PHILADELPHIA (CBS) — The School District of Philadelphia is scrapping teacher seniority rules, starting next September.

READ MORE: COVID In PA: No New Restrictions In Philadelphia As COVID-19 Cases Rising, But 'Nothing Is Off The Table'

The battle lines are drawn. Superintendent William Hite has announced plans to impose a system this fall allowing principals to fill teacher vacancies without using seniority as the sole factor.

Hite says under his plan, a committee of a school’s principal, teachers and a parent will determine teacher staffing at each school.

“We think this change is essential to enable different schools and unique school communities to match teacher skills with specific needs of students in their school.”

READ MORE: Upper Merion School District: Teachers, Staff Must Be Vaccinated Against COVID-19 Or Routinely Get Tested

The district has filed a motion with the State Supreme Court, asking the high court to affirm the district’s authority under the state takeover law to impose the new work rules.

The Philadelphia Federation of Teachers has resisted changes to seniority rules, maintaining they were a time-earned protection against administration favoritism.

This is a major test of the district’s power to impose contract terms on the teachers union. The union and the district have been unable to negotiate a new deal to replace the one that expired last August.

MORE NEWS: Report: Sixers Sign Center Andre Drummond To 1-Year Deal

PFT president Jerry Jordan in a statement said the union will fight the move in court, saying the district has chosen to forsake good-faith bargaining in favor of a legal end-around.