Complex sentence: The congregation had decided by 1918 that the school should become independent, and during Golobowsky's tenure, in 1921, it demolished the church building housing it, and built in its place a new school building, with 18 classrooms and an auditorium.
Split into simpler sentences: The congregation had decided by 1918 that the school should become independent. During Golobowsky's tenure, in 1921, it demolished the church building housing it, and built in its place a new school building, with 18 classrooms and an auditorium.