Hanging in the office of Fairfax County's Area IV school superintendent is a framed, hand-lettered birthday card from members of his senior staff. "In recognition of your need for reliable tools of decision-making," says the card. In the corner is a large silver coin.

It is an apt joke for Arthur W. Gosling, the Area IV superintendent who, by all accounts, approaches decisions -- whether on budgets or school boundaries -- more like a surgeon than a gambler.

Gosling, 48, was named March 1 to succeed Charles E. Nunley, who will leave as superintendent of Arlington schools June 30, the end of his first four-year term.

Arlington School Board members, and parents, teachers and staff members who have worked with Gosling, say his precise, methodical approach to problems of instruction and administration will serve him well in Arlington.

"He's certainly the kind of person who can come in and study something and make a diagnosis," said former Fairfax County School Board member Toni Carney. "He's very good at reorganizing his existing resources to meet the problem."

The issues Gosling will face as head of the 15,000-student Arlington school system will be vastly different from those he confronted during 4 1/2 years as one of Fairfax's four area superintendents.

The school population of Area IV is more than twice the size of Arlington's and is 92 percent white; Arlington has a 44 percent minority enrollment.

Arlington is a relatively stable system, while Area IV, the fast-growing southwestern portion of Fairfax, requires frequent school boundary changes to keep pace with rising enrollments.

"No one community mirrors another," Gosling said. "It's clearly the case that Arlington is a more diverse community, and that's one of the things that attracted me to it. I'm ready to go."

Gosling said he could not set priorities for Arlington yet -- not until he has visited schools, talked with teachers, parents and staff and given the system a critical once-over.

Gosling's supporters credit him with keeping an eye toward instruction even when highly emotional matters such as boundary decisions might have distracted him.

"Dr. Gosling is often on the cutting edge of instructional change ; he's willing to pilot things in his area," said Fairfax School Board member Laura McDowell.

The quality of instruction is Gosling's personal gauge of success, he said last week.

"The bottom line is: Do you think you've had any positive impact on what happens in the classroom? I believe we've been able to make some constructive impact on kids," he said.

Arlington School Board members pointed to an Area IV writing project and a program dubbed "The Year 2001 -- 15 Years and Counting," which encouraged critical thinking skills by having students project ideas about the 21st century, as instructional innovations by Gosling that impressed them.

Gosling said those projects also illustrated his style of management -- setting goals and challenging others to meet them.

In the writing project, different schools designed their own ways to encourage writing, from employing aides as writing tutors to launching small writing centers within classrooms. "There is no question in my mind that kids wrote more and better than they had before," Gosling said.

Also, he launched a transfer program for teachers that allowed them to switch schools or grade levels, with a guarantee they could return to their old positions after a year.

"I think that makes sense," said Marjorie McCreery, executive director of the Arlington Education Association, which represents most of the county's 900 teachers. "There's a need for the refreshment that comes with a different set of responsibilities."

Staff, School Board members and parents in Fairfax praised Gosling as an administrator who "does his homework," listens to others' opinions, readily bears responsibility and keeps those around him informed of routine matters and crises.

"I have not always agreed with Dr. Gosling, but I've always respected him," said Cathy Belter, an active Parent-Teacher Association member.

But some said Gosling's personal strengths -- his sense of humor and self-confidence -- turn into liabilities on occasion. They said his dry wit can be caustic and his sureness may come off as arrogance.

Gosling is frank in his response to these criticisms. "I'm sure I can be abrasive at times," he said. "I'm a participant; I'm not a watcher. I'm a doer. I'm not going to sit passively and let others talk. I lose my sense of humor sometimes, and that's when I'm in trouble."

Before coming to Fairfax in 1980, Gosling was assistant superintendent in South Orange and Maplewood, N.J., a 6,000-student system. He also was principal for eight years of Highland Park High School in Deerfield, Ill.

Gosling, who is married and has three children, said he will live in Fairfax until his youngest daughter graduates from high school in June 1986. Then he plans to move his family to Arlington.

"My sense is that we have a good school system here; we desire to be the best. One of the things I'll need to do is work through some kind of assessment process," he said. "It's important that we have some sense of mission."