In 1917, Elias bought stock in a Chicago jelly producer, the O-Zell Company, and moved back to the city with his family. Disney enrolled at McKinley High School and became the cartoonist of the school newspaper, drawing patriotic pictures about World War I; he also took night courses at the Chicago Academy of Fine Arts. In mid-1918, he attempted to join the United States Army to fight the Germans, but he was rejected as too young. After forging the date of birth on his birth certificate, he joined the Red Cross in September 1918 as an ambulance driver. He was shipped to France but arrived in November, after the armistice. He drew cartoons on the side of his ambulance for decoration and had some of his work published in the army newspaper "Stars and Stripes". He returned to Kansas City in October 1919, where he worked as an apprentice artist at the Pesmen-Rubin Commercial Art Studio, where he drew commercial illustrations for advertising, theater programs and catalogs, and befriended fellow artist Ub Iwerks.