 As a freshman he and his brother Chris, who was then a junior, played high school football for St. Augustine High School, but Tate was expelled as a sophomore. During his sophomore year Forcier began attending high school at the Charter School of San Diego, which did not have a football team, making him eligible to play for Scripps Ranch High School, where he completed 529-of-760 passes (69.6 pct.) for 7,448 yards and 61 touchdowns in his career. As a sophomore, he and Chris were opposing quarterbacks for a game. That season, Tate led his team to the San Diego Section Division II playoffs, and CalHiSports.com named him to the state All-sophomore team. As a junior, he led his team back to the San Diego Section Division II playoffs where they won their first game. CalHiSports.com named him to the state All-junior team. While he was in high school, he visited his brother Jason at Michigan about a half dozen times and got to know many of the players.
