"This is fascinating work," said Knight, 18. "I'm learning so much, and they give me a lot of responsibility."
Working at Keynote Systems in San Mateo, Knight's first project was to write a computer program that will help e-commerce companies test their Web sites.
"He may be a kid, but he's got a lot of skills," said Keynote's chief executive, Umang Gupta. "Our attitude is really simple: We pay based on performance, not age or other factors."
That attitude, prevalent among Silicon Valley employers, is paying off for teens. Low national unemployment is magnified in this high-tech region, where the booming information technology industry has created a vast shortage of trained computer programmers.
"If you can program, you can program. It doesn't matter how old you are, there's going to be a job," said Rich Halberg, of Joint Venture: Silicon Valley Network, a nonprofit community and business group. "I think many of these kids are going to find it hard to go back to school."
A recent Joint Venture study about the work force shortage found that 160,000 high-tech positions, roughly one-third of the industry demand in Silicon Valley, are filled by long-distance commuters from outside the region - or else the positions go unfilled.
Nationally, unemployment for all workers is also low, and jobless rates for teen-agers and adult women fell to the lowest levels in three decades.
Meanwhile, many teens growing up in the silicon-soaked culture of semiconductor chips and programming languages are becoming experts, albeit young ones, in the burgeoning industry that spawns young millionaires every day.
"It could be said that I'm like the ordinary summer teen-ager, except that I work while others vegetate," said Darrick Wong, 17, of Sunnyvale, Calif.
Wong is a "webmaster" at VIT, a Palo Alto, Calif., company, where he's building Web sites, rewriting his own programs and, in his spare time, studying to get certified in computer programming from Sun Microsystems.
He doesn't feel like he's missing out on a laid-back vacation.
"I usually look at computer work in an entirely different light," he said. "Computing is my goofing off."
During the school year, Wong's parents agree.
"They think that I should focus almost exclusively on schoolwork," said Wong. "I, however, think that if I were to do that, I'd go insane. Of course, they don't appreciate my computer development when I'm not getting good grades in school."
In the summer, however, Wong's parents - and those of his peers - are supportive that their kids are opting for high-tech jobs.
Almost 10 million American teens are woring this summer, earning about $6 an hour, according to the Labor Department's Bureau of Labor Statistics.
Of those, almost all are in the retail trade or service industry, scooping ice cream, operating amusement park rides, taking theater tickets or selling T-shirts at the mall.
Only 6 percent of teens are working in "business services," a category that includes auto repair and maintenance as well as computer jobs.
"Obviously there's not a lot of teens doing computer programming," said BLS labor economist John Stinson.
And fewer still are earning stock options.
"Yea, it's pretty cool to own part of this company. Now I'm just waiting for them to go public," said Knight, who spent some of his earnings to buy himself a computer.