 He also served on the national committee of the American Youth Congress (AYC) and the National Student League (NSL), two of the Communist Party's efforts to make inroads with American students.Matthews was also a speaker for the Unemployed Leagues, the CPUSA-sponsored mass organization directed at the unemployed, International Labor Defense, the party's legal defense organization, and the Teachers' Anti-War Conference, as well was a member of the national committees of the National Tom Mooney Council of Action and the National Scottsboro Committee of Action.Matthews visited the Soviet Union no fewer than five times during the late 1920s and early 1930s.