More like 11-12th graders
On May 25, 1935, Babe Ruth played his last major-league game as a member of the Boston Braves. Against the Pirates at Forbes Field in Pittsburgh, he went 4-for-4, had six RBI and hit three home runs. They were the 712th, 713th and 714th homers of his career.
You're mixing up two questions here. Babe Ruth hit his 712th, 713th, and 714th home runs on May 30,1935, when he was playing for the Boston Braves (his third and last team.) He retired after that game and the Braves finished last with a record of 38-115. He pretty much stopped pitching after he went to New York, pitching in a total of five games for the Yankees--three of them in his first two years; he pitched one game in 1930 and one in 1933, both of them complete-game wins. He never pitched for the Braves.