Coffield played four years of football and three years of basketball at Napa High. He was Captain of the 1924-25 basketball team which was league champion and district champion. The only loss of the season came against Stockton in the final game of the year to determine who would play for the state championship. In the 1925-26 basketball season, Coffield led the Indians to a league championship, Northwest CIF championship, and helped the team win two more playoff games before losing to St. Ignatius for the right to play for the state championship. It was the first loss for a Napa team that outscored opponents 318-163 for the season. During the 1925 and 1926 football seasons, Coffield was the star runner, passer and kicker. In games in which he played, Napa was 10-0-3 in the two years, including a tie and victory over Vallejo. In the five games that Coffield played in 1926, Napa outscored opponents 160-0. He was also Student Body President in the fall of 1926. Coffield was the standard by which other Napa greats were measured. He was arguably the best athlete to come out of Napa High during the first 50 years of its existence. Coffield went on to an outstanding two-sport career at U.C. Berkeley, where he played football and starred in basketball. He was Captain of the 1929-30 Cal basketball team. Articles in various newspapers included the following quotes:
“Young Coffield stands out as a star. This player is a demon for hard work and the speed with which he carries on and his accurate basket shooting stamps him as a top notcher.”
“Joel Coffield, one of the finest, if not the finest, basketball players ever turned out of Napa High School…”
“Coffield, by the way, is without any doubt, the greatest forward pass artist in the high schools of California.”
“Joel Coffield, Pacific Coast’s best high school passer, whirled a forward pass over 35 yards into the waiting paws of Vienop who had raced beyond the goal line.”
Coffield is the only member of the inaugural Hall of Fame class to receive ten points on every ballot.