Shan Foster was born in Laurel, Mississippi, and attended Bonnabel High School in Kenner, Louisiana.

While playing at Bonnabel his senior year, Foster garnered First Team All-State, All-Metro Most Valuable Player, All-City and All-District honors while averaging a double-double (23.4 points and 10 rebounds).

Foster's success was not limited to the basketball court, as he also made his school's academic honor roll.

[5] After picking Vanderbilt over Kansas, Notre Dame, Illinois, and LSU, Foster was immediately placed in the Commodores starting line-up.

Going into his senior year, Foster was regarded as one of the deadliest long-range shooters in the NCAA and named an All-American candidate.

Foster, with the help of freshman phenom A. J. Ogilvy, led the Commodores to their best start in school history at 16–0 before falling to the Kentucky Wildcats in double overtime at Rupp Arena on January 12, 2008.

[7] Also that season, Foster would score a game-high 32 points to lead the Commodores to a 72–69 victory over the then top-ranked Tennessee Volunteers at Memorial Gymnasium.

Foster hit nine consecutive three-pointers (including a 22-footer and a 25-footer), all of which were contested, and unleashed a career-high 42 points on the visiting 25th-ranked Mississippi State Bulldogs, including the game-winning basket, to push then 16th-ranked Vanderbilt to an 86–85 overtime victory which gave the Commodores their first undefeated season at Memorial since the 1992–1993 season.