What is the oakland museum of california? The Oakland Museum of California (OMCA) curates art, history, and natural science to tell extraordinary stories of California’s natural landscapes, human migration patterns, and its unique culture of creativity and innovation.Why should i join the museum of california? Through your Membership, you support the Museum’s mission of inspiring all Californians to create a more vibrant future for themselves and their communities. Find the Membership level that's right for you!Will omca staff be on campus during the re open? Only essential OMCA staff whose work requires them to be on campus in order for us to re-open safely and maintain capacity requirements will be onsite.