Playing at basketball powerhouse Murrah, Harrington was ranked number one or two (depending on the publication), along with Jason Kidd, as the best player in the nation.

He recorded 2,303 total rebounds in his career at Murrah, which is the second best all-time mark in high school basketball history according to the National Federation of State High School Associations (the record is 3,059, held by Bruce Williams of Florien, Louisiana).

[1] After winning Mr. Basketball in the state of Mississippi for the second consecutive year and being named first team All-American by both Parade and USA Today, Harrington was selected MVP of the 1992 McDonald's All American game as he set a game record with 21 rebounds to go along with 19 points.

Harrington accepted a scholarship to Georgetown University following fellow "big men" Patrick Ewing, Dikembe Mutombo, and Alonzo Mourning to play for coach John Thompson.

After three seasons in Houston, Harrington was traded on August 27, 1999, by the Rockets along with Antoine Carr, Brent Price, Michael Dickerson and a future first-round draft choice to the Vancouver Grizzlies as part of a three-way deal in which the Rockets received the draft rights to Steve Francis, Tony Massenburg from the Grizzlies, and Don MacLean and future first-round draft choice from the Orlando Magic, and the Magic received Michael Smith, Rodrick Rhodes, Lee Mayberry and Makhtar N'Diaye from the Grizzlies.