 He was an indefatigable champion of parental choice in education through school vouchers for students in private schools.In 1961 Blum helped to found the Wisconsin chapter of Citizens for Educational Freedom (CEF), and he was also active in the national organization, serving on its board of directors and executive committee and, for a time, as its national executive director.A popular lecturer, Blum traveled the United States giving talks to civil and religious groups, and he often contributed editorials to newspapers throughout the country.