Teachers at 10 Catholic high schools in the New York area have gone on strike after failing to reach an agreement with the Archdiocese of New York.Locally, the strike will affect Cardinal Spellman High School and Cardinal Hayes High School. School officials say the schools are still open despite the strike. The Lay Faculty Association represents about 450 teachers. The teachers have been working without a contract since September. According to teachers, salaries and benefits remain sticking points in negotiations with the archdiocese. The archdiocese has maintained it has given its best and last offer to the union.A spokesman for the union says the strike is not intended to have any effect on Pope Benedict XVI's visit to New York this week.