High school Frnka began his coaching career at the high school level. He served as the head football coach at
Lubbock High School in
Lubbock, Texas, from 1926 to 1930 before moving to
Greenville High School in
Greenville, Texas, in 1931. He led the Greenville Lions to a Texas state championship in 1933. He used the
fumblerooski for the very first time in the 1933 Texas High School Championship game.
Vanderbilt Frank left Greenville in 1936 to become freshman coach at
Vanderbilt University. He was briefly succeeded at Greenville by his assistant,
Dennis Vinzant.
Tulsa From 1941 to 1945, Frnka coached at the
University of Tulsa, and compiled a 40–9–1 record. The
Tulsa Golden Hurricane had never been to a bowl game before, and he took them to five straight, becoming Tulsa's most prolific coach. The Golden Hurricane won three league titles, and outscored opponents 1,552 to 375. He led the team to their first bowl game and a school-best national ranking of No. 4 at the end of the 1942 season.
Tulane From 1946 to 1951, Frnka coached at
Tulane University, and compiled a 31–23–4 record. Since the 1920s, the
Tulane Green Wave had been a national power in college football, and Frnka-led teams produced records of 9–1 in 1948, 7–2–1 in 1949, and 6–2–1 in 1950. In a 1949 issue devoted to a preview of that year's college football season,
SPORT magazine declared that Tulane was the best team in the country. ==Death==