Washington was born and raised in Harlem, a neighborhood in the New York City borough of Manhattan. He grew up playing basketball at Dunlevy Milbank Children's Center in Harlem. In junior high school, Washington and his friend, Ja'Quaye James, along with Jahvon Quinerly, began calling themselves "Jelly Fam." The phrase became popular among basketball players through social media and was centered around fancy finger roll layups called "jelly." Washington trademarked the name.
High school career
Washington played basketball for St. Raymond High School for Boys in The Bronx, a borough of New York City. In August 26, he shared most valuable player honors at the Elite 24 All-American Game after scoring 36 points. As a senior, he averaged 26 points and six assists per game. Washington scored a season-high 54 points in a 91–83 loss to Cardinal Hayes High School. He finished his career as St. Raymond's all-time leading scorer with 1,410 points, surpassing Darryl Bryant, and was named Mr. New York Basketball, becoming the fourth point guard to ever win the award.
Recruiting
Washington was a consensus four-star recruit and the most highly-rated New York point guard in the 2017 class. He committed to play college basketball for Minnesota over offers from several other NCAA Division I programs.
College career
On November 10, 2017, Washington made his collegiate debut, recording four points and five assists on 1-of-9 shooting for Minnesota in a 92–77 victory over USC Upstate. On February 3, 2018, he scored a career-high 26 points in a 76–73 overtime loss to Michigan. It was the highest-scoring performance by a Minnesota freshman in Big Ten Conference play since Kris Humphries in 2004. He was subsequently named Big Ten freshman of the week. As a freshman, Washington played 32 games and averaged 8.7 points, 2.6 rebounds and 2.3 assists per game, shooting 36.6 percent from the field. On December 11, 2018, during his sophomore season, he posted his first double-double, with 14 points and a career-high 13 assists in an 80–71 win over North Florida. Washington averaged 4.3 points and 2.8 assists on 31.1 percent shooting as a sophomore and received less playing time due to the emergence of Gabe Kalscheur. For his junior season, he transferred to Iona, moving closer to his hometown of Harlem to spend time with his ailing grandmother, and was granted immediate eligibility by the NCAA. In his first eight games, Washington averaged 7.8 points per game and shot 28 percent on three-pointers, but he grew more comfortable with his teammates and improved his statistics as the season progressed. On January 26, 2020, he tallied 25 pointsand 10 rebounds in a 94–88 loss to Monmouth. On February 27, Washington posted the third triple-double in Iona history with 14 points, 11 assists, and 10 rebounds in an 86–65 win over Canisius. Washington averaged 11.4 points, 5.1 rebounds, and 4.0 assists per game. On May 21, 2020, he entered the transfer portal as part of a mutual agreement with new head coach Rick Pitino and his staff. On June 15, 2020, Washington announced that he was transferring to Long Beach State, where he will sit out one season unless he receives a waiver.
