Students from about 25 area high schools will converge on George Mason High School this weekend to grapple with some of the world's toughest problems as the Falls Church school is host of its third annual Model United Nations.

Beginning at 6 p.m. tomorrow with a lecture by Neil Livingstone, president of the Institute on Terrorism and Substantial Conflict, the two-day conference features delegations from each school representing a particular country in organizational simulations. The students will try to reach international solutions to world problems as diverse as discrimination against women to the Persian Gulf crisis.

After Livingstone's presentation, students will join their committees until 10 p.m. and reconvene on Saturday for a full day of committee meetings of the Security Council, the Economic and Social Council, the Organization of American States and others. Each committee will be headed by a student from the International Relations Department of Georgetown or George Mason University. Awards, based on the accurate representation of each country's policies and other criteria, will be given to the outstanding delegates and delegations.

Event coordinator Gail Nolan said the students will gain much more than awards.

"I think first they come to realize how difficult it is to come to a compromise or an agreement among nations," said Nolan, curriculum coordinator for social studies at George Mason High School. "It's not as easy as it may appear at first. These are issues that are many-sided."

The students learn "that they can use the rules to their advantage sometimes -- and maybe not even ethically. And, finally, they learn something about international affairs," she said. "They have a grasp of at least a couple world issues."