Billy Suh has taken it easy this summer, entering just a few of the Washington area's many junior golf tournaments. However, his game hasn't taken the summer off.

Suh, a 15-year-old from Fairfax, not only won the 14- and 15-year-old age-group title in the 77th Washington Metropolitan Golf Association Junior Open today at Westwinds Golf Club, he won medalist honors as well.

He followed a 2-under-par 69 on Monday with a 74 for a two-day total of 143--four shots better than the next-best score in the 36-hole, stroke-play event.

Brent LaVigne, a 17-year-old from Brunswick, Md., made a three-foot birdie putt on No. 18 to win the 16- and 17-year-old division by one stroke. LaVigne, who works at Westwinds, finished at 75-72--147 on the 6,109-yard course. Frank Alafoginis, a 13-year-old from Bethesda, won the 12- and 13-year-old division by seven strokes with a 76-77--153.

Suh, an All-Met this past spring as a freshman at Chantilly High, finished second in his age group in the Virginia State Golf Association's junior stroke-play tournament recently.

He came into today's final round with an eight-stroke lead in his age group. Although he made fewer putts than he did Monday, when he had the tournament's only sub-par round, his margin of victory was 13 strokes.

"I was struggling on the front [nine]," Suh said. "I struggled on the back, too. . . . It's all right, but it could have been much better."

Paul Moersen, a 15-year-old sophomore at Magruder, finished second in Suh's age division. Moersen, whose top finish had been ninth in the Dewey Ricketts Cup last month, finished at 78-78--156.

Joe Scheffres, a 15-year-old sophomore at Landon, finished third in the division by making par on the first playoff hole. Scheffres won his age group in the Bobby Gorin and placed second in the Dewey Ricketts.

The competition for the 16- and 17-year-old division championship was close. Ben Hogan, a 17-year-old senior at Centreville, had a one-stroke lead after the first round. However, two double bogeys today cost him and he finished second. Sam Cohen, a 16-year-old junior at Wilson, shot a 75-74--149 for third place.