National Schools Self Advancement Through Service Concentration J.A. Rosenkranz 35 pages. Good condition. Good. Dog eared pages. Center page unsecure. The product is a softcover book titled "National Schools Self Advancement Through Service "Concentration" by J.A. Rosenkranz. Printed in 1941, this original book is written in English and focuses on the topic of national schools and self advancement through service concentration. It serves as a valuable collectible item for those interested in educational and historical literature. Founder of National Schools J.A. Rosenkranz was the founder of National Schools, an international educational institution established in 1905 in Los Angeles, California. The school was known for its correspondence courses, including English language and electronics training. It grew rapidly and faced legal issues in the 1940s, but was ultimately acquitted of charges related to defrauding the government.