Throughout his education, from primary through to tertiary level, Umehara was by his own account an indifferent student. He was in his primary school years somewhat of a daydreamer, preferring play to study. After graduating from Tokai High School in Nagoya, he gained entry in 1942 to the Hiroshima Higher Normal School, but withdrew after only two months, and, in the following year, he managed to obtain a place at the Hachikō (Eighth Rank) High School in Nagoya, under its Principal Itō Nikichi (伊藤仁吉).
Throughout his academic journey, from elementary to higher education, Umehara portrayed himself as lacking enthusiasm. As a primary school student, he often drifted off into daydreams, preferring leisure time to studying. After graduating from Tokai High School in Nagoya, he joined the Hiroshima Higher Normal School in 1942 but left after only two months. The following year, he secured a spot at the Hachikō (Eighth Rank) High School in Nagoya, under the leadership of Principal Itō Nikichi.