In 1906 , at the age of 20 , he was elected shop steward for the local brewery workers ' union .
David quit school in the fifth grade and worked in beer breweries in his teens to help support his family .
In 1906 , at the age of 20 , David was elected shop steward for the local brewery workers ' union .
David quit school in the fifth grade and worked in beer breweries in his teens to help support his family .