David Karp Quit School to Get Serious About Tumblr

But instead of trying to pry him away from his machine or coaxing him outside to get some fresh air, his mother, Barbara Ackerman, had another solution: she suggested that he drop out of high school to be home-schooled.

“I saw him at school all day and absorbed all night into his computer,” said Ms. Ackerman, reached by phone Monday afternoon. “It became very clear that David needed the space to live his passion. Which was computers. All things computers.”

Clearly.

Now 26 years old, Mr. Karp never finished high school or enrolled in college. Instead, he played a significant role in several technology start-ups before founding Tumblr, the popular blogging service that agreed to be sold to Yahoo for $1.1 billion this week. With an expected $250 million from the deal, Mr. Karp joins a tiny circle of 20-something entrepreneurs, hoodie-wearing characters like Facebook’s Mark Zuckerberg and Foursquare’s Dennis Crowley, who have struck it rich before turning 30.

“When I first met David he was 20 years old and wearing sneakers and jeans,” said Bijan Sabet, a general partner at Spark Capital, who was one of the first people to invest in Tumblr. “But I knew he was one of these rare entrepreneurs that grew up on the Web and who could come up with an idea, build it himself, and then ship it that night.”

Since founding Tumblr six years ago, Mr. Karp has been admired for his programming skills and Web site design acumen but at times has been a polarizing figure in New York tech circles because he so often blogged about his personal life and party-hopping. He has popped up in the New York Post’s Page Six Magazine, and has been a recurring target for the gossip Web site Gawker, where he was labeled a “fameball,” a derogatory term for someone who has an unquenchable desire for fame.

Tall and willowy, with a mop of brown hair and piercing blue eyes, Mr. Karp typically dresses in jeans, a T-shirt and sneakers. He speaks at a rapid clip and, often, for minutes without stopping. Technically, he never graduated from high school, which he cracked in an interview is “hopefully not a condition of Yahoo employment.”

After dropping out and working for a time in small New York tech outfits, Mr. Karp made his way to Tokyo, where he worked for several months for a start-up. He returned to the United States and became the chief technology officer for UrbanBaby, an Internet message board for parents. CNET Networks bought UrbanBaby in 2006, and Mr. Karp took the several hundred thousand dollars he made from the sale to start his own company, called Davidville. One of Davidville’s projects was a simple blogging service called Tumblr.

Mr. Karp’s run at Tumblr has not been without problems. He had trouble hiring in Tumblr’s early days, unsure how to even interview recruits. He often thought large companies were too big for their own good, proclaiming he could manage Tumblr with a team of four.

But Mr. Karp stepped out of the party scene and started dating his current girlfriend, a graduate nursing school student at New York University, four years ago. He also appeared to get more serious about his company as it grew from less than a dozen employees to more than 175 today. “David has grown up in Tumblr,” said Mark Coatney, who oversees Tumblr’s relationship with media companies.

Still, Mr. Karp’s unsure footing led to discussions about his taking a different role at Tumblr, according to two people who worked with the company and who agreed to speak on the condition of anonymity. Because revenue was not growing as fast as they would have liked, investors considered putting Mr. Karp in charge of Tumblr’s product development and finding a more seasoned chief executive.

Mr. Karp denied in an interview that there was a plan for him to give up the chief executive’s job. He said that when Tumblr’s chief operating officer left in the middle of last year, filling that job and other critical roles like head of marketing was “top of mind,” but he said there was no plan for him to step aside.

Like many who run so-called social Internet companies, Mr. Karp can teeter on reclusive. In an interview last year at the F.ounders conference in New York, he said he preferred to come to the office early to work alone, avoiding other people.

“Where I feel the most productive and engaged is when I’m buried in code, buried in some project, tweaking some designs,” he said. “I’m certainly introverted.”

Nicole Perlroth and Michael J. de la Merced contributed reporting.

Bits Blog: I.B.M.'s Watson Goes to Medical School

I.B.M., via Agence France-Presse — Getty Images Watson, I.B.M.’s question-answering computer.

Next up for Watson, I.B.M.’s clever question-answering computer? A stint as a medical student at the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University.

The collaboration, announced on Tuesday, includes a bit of controlled crowdsourcing, with the Cleveland clinicians and medical school students answering Watson’s questions and correcting its mistakes.

“Hopefully, we can contribute to the training of this technology,” said Dr. James K. Stoller, chairman of the Education Institute at Cleveland Clinic. The goal, he added, was for Watson to become a “very smart assistant.”

Part of Watson’s training will be to feed it test questions from the United States Medical Licensing Exam, which every human student must pass to become a practicing physician. The benefit for Watson should be to have a difficult but measurable set of questions on which to measure the progress of its machine-learning technology.

Yet Watson, it seems, is not an answer to the nation’s looming shortage of physicians. “We’re not going to roll Watson in and certify it as a doctor,” said Dr. David Ferrucci, the I.B.M. scientist who is the principal investigator for the Watson project.

Once trained, Watson ought to be able to help physicians cope better with the rapid pace of incoming new research. Dr. Stoller estimates that the “half-life of existing knowledge” in medicine is probably down to four to eight years on most topics. After that, it’s obsolete, or partly so.

“What we learned in medical school loses accuracy over time, and is doing so at an accelerating rate,” Dr. Stoller observed.

For Watson, medical knowledge offers a complex knowledge terrain with deep and rich information, and a multitude of interrelationships between possible causes of a patient’s symptom. Highly probable answers exist, even correct ones, but there are many possibilities and paths to a decision. The human body is not a standardized, multiple-choice test.

The goal for Watson’s artificial intelligence technology, said Dr. Ferrucci, is to move beyond simply presenting Watson with questions, and getting answers back — which it did so impressively in defeating human Jeopardy champions last year.

In medicine, he said, you have a problem with many variables. For example, a 69-year-old female with certain symptoms, vital signs, family history, medications taken, genetic makeup, diet and exercise regimens.

Someday, Dr. Ferrucci said, Watson should be able to collect and assess all that patient data, and then construct “inference paths” toward a probable diagnosis – digesting information, missing nothing and winnowing choices for a human doctor.

“That’s where we want to go with Watson,” Dr. Ferrucci said.

A Brooklyn High School Takes a New Approach to Vocational Education

The building and its surroundings in Crown Heights, Brooklyn, may look run-down, but inside 150 Albany Avenue may sit the future of the country’s vocational education: The first 230 pupils of a new style of school that weaves high school and college curriculums into a six-year program tailored for a job in the technology industry.

By 2017, the first wave of students of P-Tech — Pathways in Technology Early College High School — is expected to emerge with associate’s degrees in applied science in computer information systems or electromechanical engineering technology, following a course of studies developed in consultation with I.B.M.

“I mean, in 10th grade, doing college work?” said Monesia McKnight, 15, as she sat in an introduction to computer systems course taught by a college professor. “How great is that?”

The United States has the highest proportion of college graduates in the world. Yet many with four-year degrees are facing a transforming economy where jobs require less generalized types of education and more of the skills that many college graduates lack, in science, technology, engineering or math.

Into this breach, school systems around the country have been aiming to start new high schools like P-Tech. Officials in Chicago were so taken by New York’s school that they opened five similar schools this year with corporate partners in telecommunications and technology. Besides New York and Illinois, education officials in Maine, Massachusetts, Missouri, North Carolina and Tennessee have committed to creating such schools, and the Obama administration has recommended that Congress provide more money for vocational education — the preferred name is career and technical education, or C.T.E. — to promote this approach.

A year from now, New York City plans to open two more schools just like P-Tech, focusing on other growing industries in the city, possibly including health care. A fourth one is planned to open in September 2014. The State Board of Regents is also trying to develop assessment exams for this type of school, perhaps one that could be substituted for one of the usual Regents tests.

“When we view high-quality C.T.E. programs, we see how engaged those students are and what clear aspirations they have for their future,” said John B. King Jr., the state education commissioner. “Unfortunately, that’s not always present in some of our struggling schools.”

P-Tech, which began last year with a ninth grade and now has a 10th grade, is inside Paul Robeson High School, which is being phased out because of poor performance. Students attend from 8:35 a.m. to 4:06 p.m., in 10-period days that intersperse traditional classes like math and English with technology and business-centric courses like “workplace learning,” which teaches networking, critical thinking and presentation skills. Second-year students are offered physics and global studies as well as the business courses and college-level courses in speech or logic and problem solving — or both. There is also a six-week summer academy for geometry.

The objective is to prepare students for entry-level technology jobs paying around $40,000 a year, like software specialists who answer questions from I.B.M.’s business customers or “deskside support” workers who answer calls from PC users, with opportunities for advancement.

Stanley S. Litow, the president of I.B.M.’s International Foundation, the company’s philanthropic arm, and a former deputy schools chancellor in New York, said that the P-Tech curriculum was mapped backward: I.B.M.’s own employees were analyzed to learn what skills a student would need.

Each student also is paired with a mentor from the company, as is the principal, Rashid F. Davis; students take trips to I.B.M. facilities to learn such things as how computer chips are made; the company helped train the school’s 18 teachers, and it provides a full-time liaison based at the school to work with faculty from the New York City College of Technology and the City University of New York, which also helped develop the course work. Mr. Litow said that while no positions at I.B.M. could be guaranteed six years in the future, the company would give P-Tech students preference for openings. They would also be well-trained for other information technology jobs, Mr. Litow said.

“Because that is the problem,” he said. “Too few kids have these skills.”

Media Decoder Blog: Steve Jobs's High School Girlfriend to Publish Memoir

Chrisann Brennan was one of Steve Jobs’s first serious loves, his high school girlfriend and the mother of his daughter Lisa. Now Ms. Brennan will tell the story of her relationship with Mr. Jobs, the Apple co-founder who died in 2011, in a new memoir to be published next year. St. Martin’s Press, part of Macmillan, said on Thursday it had acquired the rights to an untitled memoir by Ms. Brennan, who is now a painter based in the San Francisco Bay Area.

After meeting him at Homestead High School in Cupertino, Calif., Ms. Brennan later lived with Mr. Jobs in a cabin, meditated with him and attended lectures. “At 17, Steve had more than a touch of the cool sophistication of a Beat poet,” Ms. Brennan wrote in an article in Rolling Stone after his death. While in her early 20s, she became pregnant and gave birth to their daughter, who is known as Lisa Brennan-Jobs. Mr. Jobs initially denied paternity of his daughter but later developed a closer relationship with her.

St. Martin’s said Ms. Brennan’s memoir would cover a range of subjects, including her relationship with Jobs, the founding of Apple and “Jobs’s enormous appeal, energy and drive as well as his developing ambition and ruthlessness in business and personal dealings.”

Palo Alto High School Club Fosters Would-Be Tech Moguls

But Mr. Slipper is optimistic. He should be. He’s just 18, a founding member of the Paly Entrepreneurs Club, an extracurricular group at the local high school that sprang into existence last September — the brainchild of about a dozen students committed to inventing the future.

“I want to build something that is tied to what is happening next,” he said.

While budding moguls in high school clubs like the Future Business Leaders of America invest make-believe money in the stock market or study the principles of accounting, the Entrepreneurs Club members have a distinctly Silicon Valley flavor: they want to create start-ups.

They have met weekly during the school year to discuss their ventures and ideas, explore matters like money-raising strategies and new markets, and host guest speakers. Once, they held a Skype chat with a software engineer in Sweden who described the intricacies of running an online music business.

Founding a company in high school is “a great opportunity,” said Vincent Gurle, 18. Later in life, “if you fail at business you might have to go live with your parents,” he said. “But we’re already doing that.”

Mr. Gurle, who will attend the University of California, Santa Cruz in the fall, started a business last year aimed at supplying students to companies as software testers. It sputtered when he could not find enough companies interested in buying the service. He counts the effort a success anyway, he told the club at a recent meeting, figuring that the people he met will remember him when he returns with his next idea.

Now he is learning how to program for Microsoft’s new mobile operating system.

Club members have been working on projects like a social network to help teenagers quickly organize study groups and a trading network for Bitcoin, a virtual currency. They have brainstormed ideas for mobile geolocation games and new kinds of grocery store scanners.

At a recent meeting, about a dozen boys gathered in an empty economics classroom at Palo Alto High, known as Paly. The demographic somewhat reflects Silicon Valley, too; there were no girls, though all the boys say they wish some would join their club.

There also were few laptops or even tablets in the room, befitting a post-PC world. All the boys had their work on paper or smartphones. They passed these around to show off their latest concepts.

Mr. Slipper, who plans to attend the University of California, Santa Barbara in January after a stint in R.O.T.C. boot camp, demonstrated his video-sharing app, speaking quickly so as to leave time for everyone to talk about their ideas before the lunch bell rang.

“The syntax wasn’t hard,” he said, explaining the coding involved. “Objective C in the iOS framework took me about two weeks to learn. I’ve modeled the business on Instagram, leveraging speed and ease of loading.” Sympathetic young heads nodded.

“How will you protect your intellectual property?” asked Aaron Bajor, 18, one of the group’s founders. He was waiting to discuss a diagram of his own project, a social network for entrepreneurs entering college.

“Someone can always copy your idea, but that will be half-baked,” Mr. Slipper said confidently. “It’s not theirs.”

James Maa, another club founder, was up next to discuss his project, the study group social network.

“We’re not out in public yet,” he said, apologetically. Mr. Maa, 18, plans to study computer science at the University of California, Berkeley in the fall. His social life, which included attending many events for start-ups, had gotten in the way of building the network, which he calls Bubble.

Not everyone had a project to present, and that was acceptable.