Robinson died April 4 after a long bout with Alzheimer's disease. He was 88.
When he retired in 1997 after 56 years at the school, he had a record of 408-165-15, and had sent more than 200 players to the NFL.
His funeral was attended by former players, coaches, a representative of New York Yankees owner George Steinbrenner -- who accepted Robinson's teams as competitors at Yankee Stadium several times -- the Rev. Jesse Jackson and numerous state officials.
The mourners began gathering early at the school's new Assembly Center for the mid-morning service.
One of the former players was Doug Williams, the first black quarterback to lead an NFL team to a Super Bowl championship. Williams led Washington to a 42-10 rout of Denver in Super Bowl XXII in San Diego Jan. 31, 1998.