Scholastic Inc. really does remain one of my favorite companies for educational material. I have to stand up and applaud them, because not only do they produce excellent materials in English, but they also strongly support bilingual education. One of my favorite sites is their Hispanic Heritage section, which includes a description of Hispanic history in the Americas, and biographical information on famous and historical Latinos. It also features a teacher's guide and activities, such as this Toma Todo game from Mexico.
Most recently they have created a bilingual newsletter with links to resources and activities for bilingual families and teachers. Teachers can also subscribe to any of their classroom magazines, some of which are also available in Spanish.