Andrew Adams is gritting his teeth in concentration as he maneuvers a mechanical claw to place a plexiglass block on a piece of graph paper.
He uses a pencil eraser to press buttons on a remote control box, easing the claw forward just a bit, then back, twisting it slightly and finally, slowly lowering the block to the paper.
Adams, a 10th grader at Wakefield High School, is one of 11 Arlington high school students in an elective robotics course, a first for Arlington and the only one of its kind in Virginia.
"You sit in a physics class . . . and you know it's necessary, but you don't really know why. Here, they see an immediate application," said Rosalie Arnold, coordinator of new programs at the Career Center, Arlington's clearinghouse for enrichment courses and adult and continuing education.
For at least two students, the application of robotics is urgent and personal.
Brian Mathis, 18, lost his left arm after an electrocution accident in 1983 and now wears an electric prosthesis. The electric arm is good, he says, but not perfect, and "Introduction to Robotics" has given him ideas for a better one.
"This is the range of movement my electric arm has," he said, bending his right arm at the elbow to demonstrate, turning his palm to the ceiling by rotating his wrist, pinching his thumb and fingers together.
"But I want to be able to have this" -- flapping his other hand as if waving goodbye -- "and this" -- flicking his wrist to move his hand like a windshield wiper.
After his accident, Mathis stayed out of school for a year. But hearing about the robotics class, he said, gave him incentive to return. "Some of the stuff I'm learning now, I want to be able to apply to prosthetic design," he said.
With the help of Apple IIe computers and MICROBOT TeachMovers -- jointed mechanical arms with rotating pincers for "hands" -- the abstract concepts of physics and calculus become as concrete as picking up a block.
The class was launched as a cooperative effort among Arlington schools; Science Applications International Corp., a Tysons Corner consulting firm that designed the curriculum, and George Mason University, which provided the teacher, graduate student Cezary Macaig.
"Half the time the robot doesn't do what you tell it to. It goes its own way. It's so frustrating," said Chris Carrington, a Wakefield High junior.
Carrington isn't sure whether he wants to make engineering a career, but Andrew Adams said he has always been interested in the field -- even before the July 1984 accident that left him confined to a wheelchair.
"I was planning on being an engineer before I got hurt," Adams said. Now, one career possibility is biomedical engineering, a field that involves the design of prostheses and medical equipment.
The robotics class is a quiet one. Students, working alone or in pairs, are engrossed in their projects, and Macaig moves easily from one to another. At a table toward the back of the room, Adams' jaw is set again. Velcro cuffs that hold his fingers together also have a slot for a pencil, so he can push buttons on the computer keyboard or remote control box.
As Adams hits the buttons, the metal claw grips a wooden alphabet block, arches across the desk and places it gently on top of the plexiglass cube. "Sometimes it doesn't go where you want it to go," Adams said, his clenched jaw relaxing into a smile. "But you can conquer anything, you know."