''BEAT STREET,'' which opens today at the Rivoli and other theaters, is designed for everybody who still hasn't had his or her fill of break dancing, or who doesn't yet understand that break dancing, rap singing and graffiti are legitimate expressions of the urban artistic impulse.
The film, directed by Stan Lathan and produced by David V. Picker and Harry Belafonte, has a small, modest story about some South Bronx kids who are attempting to dance, rap and spray paint their way to fame and fortune. Among its talented young performers are Guy Davis, the son of Ossie Davis and Ruby Dee, who plays a disk jockey with a special gift for the rhymed improvisation that's called rapping; Rae Dawn Chong, the daughter of Tommy Chong of Cheech and Chong, as a university music major; Jon Chardiet, as a graffiti artist who swoons with excitement every time he sees a subway car that hasn't yet been decorated, and Robert Taylor, as a very young, very gifted break dancer,
The film's melodrama adequately supports the nearly nonstop music and dancing, but the film itself is best understood as a trailer for the soundtrack album, the music for which was produced by Mr. Belafonte and Arthur Baker. If the album catches the intensity and wit of the film's big finale, it should be a smash.
''Beat Street,'' which has been rated PG (''Parental Guidance Suggested''), contains some vulgar language.
-Vincent Canby / The New York Times / June 8, 1984