Cheng Shan-hsi taught Chinese painting for many years at NTNU, and though now formally retired, he still teaches a few classes at the NTNU graduate school of fine art.
在師範大學美術系國畫組任教多年，如今雖已正式退休卻仍在師大美術研究所兼課的鄭善禧，不論所學、所教、所畫都不劃地自限。