The first dual immersion program in the Petaluma City School District, and the second of its kind in the city , opened to students Tuesday as the school’s teachers and administrators look forward to a new and diverse era of learning. McDowell Elementary School, which opened in 1958 at 421 S. McDowell Blvd. , is now offering curriculum in two simultaneous languages — English and Spanish — for students starting in kindergarten through second grade, alongside its traditional English-speaking K-6 classes.