Dickinson was named a consensus second-team 2021 NCAA Men's Basketball All-American as a freshman for the 2020–21 Big Ten regular season champion Michigan Wolverines.

Dickinson transferred to Kansas as a senior, where he was a 2024 NCAA Men's Basketball All-American and a first team All-Big 12 Conference honoree.

[3] By April of his freshman season, he had offers from Penn State and Notre Dame as well as interest from many top programs.

Then Dickinson helped DeMatha win the Maryland private school championship on March 6 against Rock Creek Christian Academy, scoring 31 points in the 64–58 victory.

[9] Following his sophomore season, he was considered (along with Jeremy Roach) one of the two best players in the DC metro area class of 2020,[10] with USA Today ranking him 18th in the nation.

[17] As a senior, Dickinson averaged 18.1 points, 10.3 rebounds, 3.8 assists and 2.1 blocks per game, leading his team to a WCAC title.

[22] In July, Dickinson listed the top 7 contenders for his services: Purdue, Florida State, Louisville, Michigan, North Carolina, Notre Dame and Providence.

[24] By the time he cut his list to Duke, Florida State, Michigan and Notre Dame in October, he was ranked 34th by 247 Sports.

[30] Dickinson and Timberlake led DeMatha to a 70–56 WCAC championship game victory over the Roach-led Paul VI Catholic High School.

[40][41] However, on April 9, Castleton (who had lost the role as Jon Teske's backup to Davis) decided to enter the transfer portal.

[44] On December 20, 2019, he committed to playing college basketball for Michigan over offers from Duke, Florida State and Notre Dame.

[47] Dickinson averaged 13.0 points, 9.0 rebounds and one block per game and shot 73.3 percent from the floor (11-for-15) in wins over Ball State and Central Florida.

He helped Michigan extend its list to three straight years with a player on the All-Freshman team, joining Ignas Brazdeikis (2019) and Franz Wagner (2020).

[66][67] For the third time in school history (Juwan Howard/Jalen Rose (1993-94) and Mitch McGary/Glenn Robinson III (2013-14)), Michigan had 2 Preseason All-Big Ten honorees as Dickinson was named along with incoming freshman Caleb Houstan.

[69] He posted a career-high 33 points in the rivalry game against Michigan State for interim coach Phil Martelli in an 87–70 victory on March 1.

Michigan was led by Dickinson with 27 points, including 3-of-5 on three-point field goals, 11 rebounds, four assists, a block and a steal.

[82] On November 8, 2022, in a 75–56 victory over Purdue Fort Wayne, Dickinson recorded a game-high 22 points and 12 rebounds, for his 18th career double-double.

With his 31 points, Dickinson surpassed current head coach Juwan Howard (1,526) for 20th on Michigan's all-time scoring list.

[94] On March 18, during the second round of the 2023 National Invitation Tournament, Dickinson recorded 21 points and 11 rebounds, for his 31st career double-double.

[99] He was regarded as the top rated men's basketball player (ahead of Max Abmas and Kel'el Ware) in the portal in 2023.

[100][101] Dickinson took unofficial visits to his hometown programs Maryland and Georgetown who both had changed coaches since his high school recruitment.

Michigan's failure to make the 2023 NCAA Division I men's basketball tournament, and its dim championship prospects was one speculated reason.

Another was the likelihood that he could procure a superior Name, image and likeness compensation package, despite his endorsements with Lowe's, Ritz Crackers, and Outback Steakhouse.

[112] Dickinson got off to a fast start at Kansas, earning Big 12 Newcomer of the week on November 13, for averaging 19.5 points and 8.0 rebounds in his first two games.

[113] On November 14, 2023, Dickinson took advantage of a Kentucky Wildcats lineup that was without 7 foot (2.1 metres) big men Aaron Bradshaw, Ugonna Onyenso and Zvonimir Ivišić.

[114][115] He was the first Big 12 Player to accumulate 25+ points and 20+ rebounds in a game against a ranked opponent since Blake Griffin on November 18, 2008 for Oklahoma vs. No.

[118][119] On February 5, Dickinson earned a third Big 12 Player of the Week award, when he collected his 2000th point as he helped Kansas defeat Oklahoma State and No.

[122] Dickinson became the 17th consensus All-American for Bill Self as coach at Kansas, marking the school's third consecutive season with such a recognition (Ochai Agbaji in 2022 and Jalen Wilson in 2023).

[139] His older brother Ben played college basketball for NCAA Division I Binghamton, Loyola Marymount and UNC Greensboro.

[140] Ben (6 ft 9 in (2.06 m)) who attended Gonzaga High School and was a 2011–12 America East All-Rookie Team selection, also played as a graduate student for NCAA Division II Cal State San Marcos.