WASHINGTON - 'Avatar' director James Cameron urged young Americans Monday to pursue careers in science and technology to keep the United States at the forefront of technical innovation -- and allow him to make more blockbuster movies.

Science, technology, engineering and mathematics, or STEM, "are where this country has to continue to lead," Cameron said at the US finals of the 8th Microsoft Imagine Cup, where students presented projects they developed that use technology to fight global problems.

"We can't fall behind in that area. We need engineers, we need innovators," Cameron said, adding that 'Avatar' would not have been made without innovative technology developed by Microsoft and the out-of-the-box thinking of a young team, average age 23, who put the technology to work in the movie.

The Imagine Cup aims to inspire young people from around the world to become tomorrow's technology and business leaders, Microsoft chief research and strategy officer Craig Mundie said.

"The technology industry not only is a key driver of economic growth and job creation but also offers vast potential to solve some of the world's toughest societal problems," he said.

Eighty students out of a starting field of 22,000 made it to the US finals of the Imagine Cup, presenting projects that dealt with everything from pollution to pediatric illness to poverty.

The winner of the software division -- a project called Mobilife, by students at the University of California, Davis -- will travel to Poland in July to compete against teams from more than 150 nations in the world finals of the Imagine Cup.

Mobilife uses the Windows Mobile platform and computer-assisted microscopy to allow doctors who work without the benefit of the facilities of a modern hospital -- such as field doctors in sub-Saharan Africa -- to detect vascular diseases in children, including diabetes, hypertension and sickle cell anemia.

The game design division was won by a game called "Sixth," which raises awareness of the issue of global poverty by putting players into the skin of a child in a slum in India who has to battle his way past obstacles to collect water for his family.

"Sixth" was developed by students at the two-year Central Piedmont Community College in North Carolina, who beat out academic big hitters like Ivy League university Yale to take top honors in their division.