The Rainbow Warriors (7-4) play Pepperdine Tuesday in the fifth-place game. The Colonials (6-4) will meet Coppin State in the seventh-place game.
George Washington was held to just 18 first-half points and was outscored 42-29 in the second half.
Hawaii led by as many as 29 points. Petras Balocka had 14 points and Lasha Parghalava added 10 for the Rainbow Warriors.
George Washington, which shot just 30 percent from the field, was led by Travis King s 10 points. The Colonials attempted just 15 free throws to Hawaii s 33.
Flemings had 13 points and seven rebounds by halftime to send Hawaii into the break with a 31-18 lead.