Prince George's schools will teach a special system-wide course to 111,000 students returning to classes next Monday. It is called, "How to Make Do With an 11 Percent Across-the-Board Budget Cut."

The first thing all students will learn is that more than 80 percent of the budget goes to pay salaries, mostly those of teachers. Classes at every level will be a little more crowded because 507 teachers were laid off last June. Elementary school students will learn that one physical education and one music period per week have been cut to save $695,000.

The elementary school lesson will include fractions. Exactly half of the elementary librarians will be gone, with schools this year getting the services of librarians every other week. The maximum walking distance for some 3,200 elementary students will increase by one half also, to 1.5 miles, before they are eligible to ride the school bus.

School board president Doris Eugene shed tears when $37 million was cut from the schools in June because of a tight county budget forced by the TRIM property tax limitation. Superintendent Edward J. Feeney hopes the value of the lesson in county finance will not be lost on the students' parents.

"They certainly have to be acquainted with the facts of life, and it isn't just restricted to Prince George's County," Feeney said in an interview. "The budget fight certainly isn't over. There is never an end to pressure in education."

Indeed, pressure on Prince George's teachers will increase as they are asked to do more with less. The teachers will begin negotiating a new contract this fall, and Feeney expects job security to be high on their list of priorities. The morale of an older teaching force, one whose prospects for advancement have been limited by the shrinkage in the system, may suffer.

"Some of the people have taken it better than others, there is no doubt about it," Feeney said.

Making do means an overall cut in materials this year, from badly needed audio-visual equipment to already scarce construction paper. And because of a moratorium on all new text and library volumes, "there clearly won't be that joy of cracking open a new book either," said Edward Felegy, assistant superintendent for administration.

Money for playing was cut more than for school work. A 40 percent slash in the athletic budget will halve the number of junior varsity contests, cut coaches in all sports except varsity football, and reduce equipment purchases. The school board also authorized seven foreshortened "game bell" days per school to allow students to attend interscholastic contests and thereby boost revenues. On game bell days, the bell rings a little early to end each class period, resulting in a shorter academic day.

Despite these trims, the system takes pride in a handful of major improvements to the educational program. These include:

* The opening of a second Science and Technical Center at Oxon Hill High School, patterned after the unusual program at Eleanor Roosevelt High School. Gifted students who live south of Pennsylvania Avenue will enter a new wing at the recently renovated Oxon Hill school. The students, selected by competitive exams, no longer will have to make the long bus ride to Greenbelt to attend Roosevelt.

* The new Forestville High School will become the county's 20th, relieving overcrowding at Suitland High School. The closed Spaulding Junior High and Forestville elementary schools were renovated at a cost of $594,000 and joined by a 150-foot elevated walkway to make Forestville High. The new high school will accept 800 students from the present Suitland attendance area.

* Five more junior high schools -- Andrew Jackson, Benjamin Stoddert, Francis Scott Key, Martin Luther King and Thomas Pullen -- will become two-year middle schools this year. With their switch to a seventh and eighth grade program geared to meet the special needs of pre-teens, middle schools will outnumber junior high schools for the first time since the conversions began two years ago. The shift will bring the number of middle schools to 17, leaving 15 junior highs.

* Tough new rules on alcohol and drug abuse as well as weapons possession in school go into effect. A second alcohol or drug offense will draw mandatory expulsion, and a requirement that a student receive drug rehabilitation treatment before he or she can be considered for readmission. Expulsion also will be mandatory for any student caught with a weapon in school.

* The pilot "Primary Project," which uses language techniques originally developed for handicapped students to introduce reading in kindergarten, will be expanded county-wide this year.

County Executive Lawrence J. Hogan has insisted that volunteers can and should take up the slack caused by lost teachers. Some schools will make out better than others.

"Fortunately, I've had a number of parents who will come in and volunteer," said Seat Pleasant Elementary Principal Julia H. Goodson. Goodson was also lucky enough to have a riffed teacher, Carol Debernardinis, offer to do for free what she did for money last year.

"Words cannot express how I felt when she said she'd come back to me," Goodson said.

At Rogers Heights Elementary, Principal Charlotte Mason has had only one parent volunteer so far to help run the school's huge library, which will have a professional librarian on alternate weeks only. At the same time classes are running between 29 and 33 students per room compared to 24 to 29 last year, "and we have not really begun to register yet," Mason said.

"It looks like class sizes are going to be pretty large. It makes a big difference in the amount of individual time teachers will be able to spend and in teaching strategy," Mason said.

"How do you do more with a loss of staff?" asked school spokesman Brian J. Porter. "Everybody works harder. It's not a particularly easy thing to do, but we're trying."