For over 50 years Sifu Bill and Mary Owens have owned and operated Cascos Martial Arts Academy in East Oakland. They have specialized in teaching self-defense, cultural awareness, educational values, and self-confidence to students of all ages. But the COVID-19 pandemic has nearly brought down the dojo located at 7415 MacArthur Blvd. By Post Staff For over 50 years Sifu Bill and Mary Owens have owned and operated Cascos Martial Arts Academy in East Oakland. They have specialized in teaching self-defense, cultural awareness, educational values, and self-confidence to students of all ages. But the COVID-19 pandemic has nearly brought down the dojo located at 7415 MacArthur Blvd.