Arco Iris Spanish Immersion Charter School | 102 followers on LinkedIn. Arco Iris is a public Spanish immersion school based in Beaverton, Oregon and is Beaverton's first Charter School! | Arco Iris Spanish Immersion School is a K-5 , public charter school in the Beaverton School District. Our school is a place of great teaching and joyful learning; a community that joins together to raise up our children to be responsible, bilingual, and multicultural citizens.