Kentucky banjo man Doc Hopkins, one of the many outstanding traditional performers who will be featured at next weekend's 44th Annual National Folk Festival, which has been at Wolf Trap for the last 12 years, is quite proud about one of his prize pupils, Stephen Wade, whose "Banjo Dancing" is entering its 79th week at Arena Stage's Old Vat Room. During the '30s and '40s, Hopkins had been a star performer on WLS' National Barn Dance radio shows out of Chicago, where he used get "a terrific lot of mail."

In the '50s, Hopkins gave lessons to Fleming Brown, who eventually became a teacher at Chicago's Old Town College of Folk Music, where he in turn took on a promising young student named Wade.

"Stephen got to be quite a terrific banjo player, but he played that wild fast stuff, what we call thrashing mountain style. I worked on him to develop his finger work on the banjo," Hopkins recalled. The two of them played duets at Chicago clubs, "and we practiced at Steve's home for a whole year. He didn't feel like he was ready to play in public, but I finally got him going. And now there's no stop," added Hopkins, now 82. Wade has taken three weeks off from his "Banjo Dancing" duties, partly to show Hopkins the town. The "Doc," incidentally, came not from a degree or from the medicine shows Hopkins traveled with, but because he was the seventh son and, in mountain lore, he was destined to become a healer. The festival runs Friday through Sunday. Call 296-0068 for information.