Teachers at three Catholic elementary schools in Westchester staged a sickout Friday.The sickout was at Sacred Heart in Hartsdale, Blessed Sacrament in New Rochelle and Our Lady of Fatima in Scarsdale. Teachers at seven other Catholic schools in the New York City-area also took part.The sickout was part of the ongoing dispute between the New York Archdiocese and the teacher unions. Among the main sticking points are teacher salaries and the cost of health insurance.On Tuesday, the Lay Faculty Association approved a strike at 10 Catholic high schools when Pope Benedict XVI visits New York later this month. Friday's strike was by members of the Federation of Catholic Teachers union.Catholicschool teachers threaten strike for pope's visit