Library of Congress has abundance of primary sources and resources for classrooms. To make it easier for teachers, they also have sets of "themed collection," a collections of related primary source sets so you don't have to search for multiple primary sources related to one topic. They have already gathered the related primary sources for you.
https://www.loc.gov/search/?in=PartOf%3ATeachers&q=asia
http://www.loc.gov/teachers/classroommaterials/themes/asian-pacific/exhibitions.html
Multimedia resources from the Library of Congress that support instruction about Asian Pacific Americans.
These resources include expert presentations, exhibitions, bibliographies, Webcasts, and other online materials.
The above links hav a list of Asian-American themed collection. Once you click on one site, it may not look like there are much for teaching materials, but there are multiple hyperlinks which could take you to more primary sources related to topic you are searching. When you click on the image, it will show you the meta data on that primary source. Some themed collections will also have a lesson plans already there for you. The hardest thing about navigating Loc.gov for teacher material is that they have so much resources, it is time-consuming.
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