In the past year, education-reform icon Sal Khan has been lauded by Bill Gates as the "teacher to the world" and has been listed among Time magazine's 100 most influential people.
His Silicon Valley-based Khan Academy posts free videos -- most of which star Khan himself -- and offers accompanying questions on everything from addition to calculus to art history. As of this month, Khan Academy had tallied more than 177.2 million views of its lesson pages and is being used by traditional and charter schools, as well as individuals worldwide.
Amid the adulation, some teachers now have piped up with criticism of his teaching methods. While they admire the website's accessibility and fun, the question sets and teacher "dashboard," they criticize lapses in content, a shortage of explanation and occasional leaps in logic. And, they say, the collection of eight- to 10-minute videos skips the heavy-lifting part of teaching, focuses on procedures over concepts, and doesn't ensure that students understand what's being taught.
To drive home their point, Michigan professors David Coffey and John Golden posted a video, "Mystery Teacher Theatre 2000," poking gentle fun at a Khan lesson on how to multiply and divide negative numbers. (Khan then took down his original video and posted a revised one.) Other educators created what they've abbreviated as the MTT2K contest. Dan Meyer, a Stanford University doctoral candidate in education, and Boston-based blogger Justin Reich are taking on Khan on his own territory, offering $750 in prizes for the best online critique of Khan Academy videos. The deadline is Wednesday.
Of course, questioning Silicon Valley's most recognizable name in education comes with a price. Critics have been accused of being bitter, jealous and worse. MTT2K Episode 1 on YouTube elicited more dislikes than likes. Khan's popularity derives not only from the brilliant simplicity of his videos and tools for teachers to track their students, but also from his status as an outsider challenging the often-derided education establishment.
The likable and disarming Khan has a lofty ambition: Make "world-class education" accessible to everyone. That, he said, would combine a deep understanding of concepts and skills while fostering creativity and originality.
A holder of three bachelor's degrees from the Massachusetts Institute of Technology and an MBA from Harvard University, Khan has personally recorded 3,000 of the nearly 3,300 videos on the Khan Academy site. "The real draw for me was always to be able to explore the world and understand it and distill it down, so that it's truly conceptually intuitive," he said.
He has attracted millions in funding from Google, Gates and other foundations. Word of Khan Academy spread virally, then among math teachers and other educators, and more recently through major media.
Critics stress that they admire much of what Khan has done. "I'm a huge fan of Mr. Khan," said Coffey, a 25-year teaching veteran. The lessons are accessible 24/7 to anyone with a computer and Internet connection. Like online games, Khan Academy offers students coveted virtual prizes for correctly answering its questions. It equips teachers with a sophisticated "dashboard" for tracking each student's progress.
But lessons sometimes fall short. On the video ridiculed by Golden and Coffey, Khan didn't explain why multiplying two negative numbers produces a positive number, misnamed one mathematical rule (the commutative property) and inconsistently assigned positive signs to numbers. Besides minor errors, critics worry that the Khan Academy suite, used alone, promotes a shallow understanding of math.
"It's easy for students to feel successful just repeating a computation they see somebody else do, while not constructing an understanding of the procedures involved," Golden said.
Khan touts his "flipped model" of teaching: Students watch videos on their own to learn new material, then spend class time working with teacher supervision on problems that traditionally would have been assigned as homework. But, Coffey said, that model sticks with the old-fashioned I-talk-you-listen mode of teaching. Of Khan, he said, "simply doing a lecture on video isn't all that innovative."
Math teacher Hye Lee Han, in San Jose's Evergreen School District, this summer had her class of struggling students preparing for eighth-grade algebra skip the videos and just tackle the Khan questions. She was using Khan Academy for the first time, to supplement her lessons.
"I love it," she said about Khan. What she really likes is the color-coded, real-time spreadsheet showing each student's progress, including the number of attempts at solving each problem. "I can keep track of them, who's mastered it, who's struggling," she said.
Likewise, students love Khan's virtual rewards for completing problems.
"It makes the class funner," said Taea Regua, who will start eighth grade at Quimby Oaks School this month.
Classmate John Tortolano agreed. With more points for correct answers and winning streaks, "you get to change your cover picture and you can get better stuff" -- including icons and virtual prizes.
Independent, comprehensive assessment of Khan Academy's effectiveness awaits an SRI International study to be released this fall. The Los Altos School District has relied mostly on internal data and observation in deciding to expand a Khan Academy pilot to all fifth- through eighth-grade math classes this year. But the district doesn't embrace the whole program. "The videos are the least impressive part," Assistant Superintendent Alyssa Gallagher said. "We are not suggesting replacing a teacher with a video lecture."
A review published in December by Stanford and others of a Khan pilot with Envision Schools in Oakland found that students using Khan did only marginally better than students in regular math classrooms. Correct answers increased by 6.4 percent among Khan students during the course, compared with 5.2 percent by non-Khan students.
Critics hope their points will help Khan improve his site and lessons.
It seems that they're being heard. "On a daily basis we're getting tons of feedback," which prompts immediate changes, Khan said. "We are actually a quick platform for experimentation."
Khan started creating tutorial videos eight years ago to help his then 12-year-old cousin in Louisiana. After posting them on YouTube, he attracted a following that has grown exponentially. He expanded his repertoire, quit his job as a hedge fund analyst and created lessons full time. He draws on research from all over and doesn't read from a script in his videos.
"Good communication," he said, "comes from a person's mind."
Contact Sharon Noguchi at 408-271-3775. Follow her at Twitter.com/noguchionk12.