Hall transferred to WVU from Compton Community Junior College, where he had been associated with winning basketball for two seasons. Compton Coach Jim Newman described Hall as possibly the best point guard to have played at Compton. Compton's 54-14 record poke for itself as Earnest led the team to one state junior college title and one second place finish. Hall was named Most Valuable Player in the state junior college tournament his freshman year at Compton as they rolled to the championship. His sophomore year, they again reached the finals but finished second. Hall was an excellent ball handler and averaged 13.6 points per game his sophomore year. He led his team in assists, averaging seven per game and also added 4.2 rebounds a contest. That same year, Hall was named captain of the California AAU All-State team and earned a place on the first team all-Western State Conference squad.

He transferred to WVU for his junior year and it was believed that Earnest would add immediate backcourt help to the 1974 team. He was considered the type of player who made things happen in addition to having the ability to see and hit the open man. He was also an excellent passer and dribbler. Earnest lived up to his advance billing as he broke into the Mountaineer starting line up leading the squad in assists, maintaining a good scoring average and directing the WVU offenses. "LA Slim," as he was known, started all 27 games for the Mountaineers and led them in assists with 91, outdistancing his closest teammate by 16, and contributed 271 points for a 10-point average per game. Hall also connected on 45.1 percent of his field goal attempts and shot 67.7 percent of his foul shots. He also added 107 rebounds, fourth best on the squad.