Van Morrison. If sound movies had been invented two years ago, the first talkie, The Jazz Singer, would have featured Van Morrison. He is one of the least predictable, most innovative singers of rock--as inimitable in his own way as Dylan. How he wound up in Harvard Square Theater is a mystery. But he will be there tonight. Pray that he sings "Tupelo Honey." Thursday, March 14 at the Harvard Square Theater, 4:30 and 8:30 p.m., $4.

Bound for Glory. Michael Cooney is one of the best contemporary singers of American music. Few know more about the songs they sing and few turn their knowledge into more memorable performances. He is a fine guitarist and banjo player, a splendid raconteur, and a light, engaging singer. The proceeds from this tribute to Woody Guthrie, which Cooney will narrate, will go to research on Huntington's Disease, which took Guthrie's life. The show should be a rare treat. Saturday, March 16 at the Brookline High School Auditorium, 8 p.m., $2.50.

Folk Notes. Dave Buskin, a very good guitarist, songwriter, and singer plays Passim this weekend. Through Sunday, March 17. Call 492-7679 for information...Roger McGuinn, out on his own since the Byrds flew their separate ways, graces The Performance Center with his picking and singing. The Ozark Mountain Daredevils play with him. Through Saturday, March 16, 8 and 10:30 p.m. Call 876-4531 for information.

Donny Hathaway. Hathaway is a superb pianist and soul singer whose single "Where Is the Love?" with Roberta Flack only hinted at his talent. Through Sunday, March 17 at Paul's Mall. Call 267-1300 for information.

Sahara. Those in search of a lively dance band right here at Harvard might do well to try out a free concert by this eight-piece group featuring lots of brass and percussion, the usual guitars, bass, and piano, and a female lead singer. Some of these folks were members of at least one of Cambridge's better groups of the last few years. And surely, the price is right. Friday, March 15 at the Hotel Continental Ballroom, 8:30 p.m., free.