By most conventional high school standards, girls who are 5-foot-3 are not supposed to be great jumpers. But Myrtle Chester is not a conventional athelte. She is a versatile and multi-talented track and field performer at Laurel High School in Prince George's County.

From the day a gym teacher took notice of her remarkable skills in a ninth grade class, Chester has blossomed into one of the most outstanding athletes in the county.

She has high jumped 5-9; she has long jumped more than 19 feet; she has run a fast 14.2 in the 110 hurdles and turned in a personal 2:15.9 in the 880-yard run.

She is a pentathlete, that rare breed of performer who can excel at both track and field events.

At the University of Maryland's Whomen's Invitational earlier this year, Chester amassed 3,702 points in the pentathlon, to take first place.

Track and Field Magazine has ranked her as one of the top pentathletes in the country, and among the top 10 in each of her events.

Many of her competitors are considerably taller than she. According to her coach, Rick Grabisch, Chester has a special blend of spring and quickness that compensates for her lack of height.

"She has the perfect combination," he said. "She has incredible spring for her size. You look at her and it doesn't seem likely that she can jump the way she does. From the very first day I saw her, I knew she was something special."

Chester's development has been carefully nurtured by Grabisch, who has been at laurel for five years.

"We looked at what she had to do and set up a timetable for her development.

Then we set certain goals in terms of her competition so that we could get the most out of her ability," he said.

Grabisch added that Chester is actually ahead of schedule.

She presently holds seven school records and with the coming state championships on Saturday, she appears on the verge of capturing even more.

Chester continued her dominance in Prince George's County last weekend in the Maryland AA Region meet at Eleanor Roosevelt High School. She took the 100-meter hurdles (14.9), the 300-meter hurdles (46.2), the long jump (18 feet, 1 inch) -- a meet record -- and the high jump (5 feet, 7 inches).

Grabisch admitted that others have been instrumental in Chester's growth as well.

"She is so mature in her training that she can assimilate a multitude of advice from other coaches without losing concentration. Besides, I wouldn't be fair to her if I didn't allow her to accept advice that would enhance her future."

Chester, 17, a native of Guyana, is the youngest of 11 children and the first in the family to participate in sports -- something she is particularly proud of.

Although she is still a citizen of Guyana, she and several other members of the family are living here with her father, Rufus W. Chester, a production operator for Electro-Therm Inc. Her mother died six months ago.

Chester works part time at McDonald's during the week and babysits on weekends when she is not traveling or competing in area meets. Despite an arduous schedule, she is on the dean's list at Laurel.

"I guess it could be difficult," she said, "but I am motivated by achievement in life. That's why I make the sacrifices."

Because of her outstanding academic and athletic prowess, Chester has been wooed by such track powers as Rutgers, University of Pittsburgh, University of Maryland, Villanova and University of Tennessee. She says that her selection will depend first on the school's business program -- she wants a career in business administration -- and then on the coaching staff.

Chester has been more places than most athletes her age: to England, Paris and Scotland on foreign study trips, and recently to Bermuda to compete in the Caribbean Games as a representative of Guyana. The government of Guyana invited her to represent the country in the games.

She captured three of Guyana's five medals, winning a gold medal in the long jump (19 3/4 feet) and a bronze in both the high jump (5-5) and the hurdles (14.96).

Her feats there have prompted the once reluctant Guyanese government to sponsor her as a possible representative in the Olympic trials.

Coach Grabisch admits that his talented pupil has "forced me to learn. She has so much ability that I have to be well aware of the finer points of training. I have learned a great deal."

Chester credits her coach with helping her realize her potential. "But more importantly, he has helped me grow up."

Chester says her goal is to improve her time in the 100- and 300-meter hurdles, gather 4,000 points in the pentathlon and get up over 20 feet in the long jump. With her determination and Grabisch's tutelage, it can be considered a reasonable expectation.