Although Yim took over the Chung-Ang Training School for Kindergarten Teachers (Normal School) and provided land for its building, the school still lacked teaching facilities. Moreover, Yim had financial problems in operating the school, especially when the Japanese banned donations to it. Nevertheless, Yim rented Pearson Bible School building to start the Chung-Ang school. The school also received financial support from the United States' Pfeiffer Foundation as a result of Yim's endless efforts to raise funds in the U.S.
In 1938, Yim built the school’s first stone-building, Young Shin Hall, which eventually became Chung-Ang’s permanent home. Most of all, Chung-Ang Training School for Kindergarten Teachers (Normal School), which developed the philosophy of kindergarten education, became the cradle for "new women." These women founded the Chosun Kindergarten Education Society and took on active roles in social education through concerts, plays, and literary activities
In 1937, the Japanese waged war against China and brought about a war in the Pacific by attacking Pearl Harbor. In 1940, they closed down Dong-A Daily News and Chosun Daily News. Then they announced a detention law against political offenders in 1941, established a conscription system, and promulgated the law for wartime emergency procedures in 1943. The Japanese heavily repressed Chung-Ang Training School for Kindergarten Teachers (Normal School), targeting Ms. Yim, who was a Christian and who received education in the U.S. Although the imperial Japanese attempted send a signal by attacking the school, their forces couldn’t enter the school due to Dr. Yim's efforts. However, as a result, the Chung-Ang school was banned from accepting applicants and eventually was closed down in 1944.