Yury Lifshits is working on algorithms and prototypes of new services at Yahoo! Research. Before that he was teaching university courses in the U.S., Germany, Russia and Estonia. He blogs at yurylifshits.com and publishes his teaching materials at yury.name/teaching.

Education technology has become a busy space in recent years. Mark Zuckerberg and Bill Gates continue to push the envelope with enormous philanthropic gifts toward education reform; Blackboard.com was traded at a $1 billion plus valuation; and Google is putting millions into education tech sites like KhanAcademy. At Mashable, you've read about social campaigns for education, gaming in education and free educational resources.

With so many startups on the scene, it is easy to get lost. Fortunately, most innovation is centered around a short list of fundamental ideas. In this post, we'll walk through nine clusters of education tech companies.

1. New Institutions







The education system of the 20th century is built around institutions: schools, colleges, academies and universities. Naturally, many companies are aiming to recreate a degree-issuing institution. In this scenario, a startup has the highest level of control and the highest earnings per student. Online-based institutions have started from several niches (education for children with disabilities, advanced placement programs, test preparation) and are approaching mainstream education.

We've now seen the first online high schools (Keystone School), colleges (University of Phoenix, Kaplan University, The Open University, University of the People), certification programs (Alison.com), enterprise training programs (GlobalEnglish.com), art schools (AudioVisualAcademy.com) and test preparation programs (Top Test Prep, GrockIt, Knewton, RevolutionPrep, TutorJam, BrightStorm).

At the same time, brick-and-mortar institutions launch experimental online programs. iQAcademy helps high-schools to offer online classes, and 2tor and Altius Education do that for universities. Finally, there are innovative offline programs like YCombinator, Singularity University and Tetuan Valley.

2. Learning Management







To build a new educational institution, one needs to assemble a lot of pieces. Institutions are also hard to scale. That's why many companies are opting for a different path: They focus on a single problem, create a software solution and sell it to schools.

Web-based tools are now used to manage applications, grades (Schoolbinder, LearnBoost), class ratings and reviews (Courserank, acquired by Chegg), schedules, tests, textbooks and student-teacher messaging. There is also a market for content management (Sakai Project, Moodle).

Another important area is analytics and reporting systems (SchoolNet.com). Learning management systems are present in every market: schools, universities, corporate education and training centers. Notable examples include Blackboard, Koofers, ePals, MyEdu.com, edu20.org and GlobalScholar. Solutions for corporate learning include LearningZen, Learn.com, Taleo.com, eLearning Brothers and Mindflash.

3. Online Content







For a long time, the market of educational content was controlled by book publishers. Technology is ready to disrupt that picture in several ways. Online video is set to take a share from text-based learning. Recommendation and search systems are offering new ways for content discovery. As in other forms of content, sales and subscriptions are moving to the web. TED.com, Big Think, 99 Percent, Pop!Tech, GEL Conference and the Charlie Rose show are notable for video recordings of technology and business leaders. Academic Earth, Videolectures.net, and ResearchChannel.org do the same for the science community. Salman Khan of KhanAcademy.org recorded more than 1,000 instructional videos covering almost all of the secondary school curriculum.

MIT OpenCourseWare and Stanford eCorner are leading examples of free online content from top universities. Tools for publishing (and charging for) online educational content include Faculte.com, uDemy.com, Videolla.com, LearnOutLoud and LeapingBrain.com. Youtube.EDU and iTunes U are general purpose content distribution hubs. OERCommons.org is a search engine for open-licensed content. Sites like About.com, HubPages, Instructibles, AssociatedContent and eHow collect practical advice on everyday topics.

Using the principles that power Wikipedia, everyone can now create their own wiki with platforms like PBWorks or Wikia.com. Wikified educational content can be found at Curriki.org, Wikiversity.org and Wikibooks. Content libraries are created for career inspiration (dailyendeavor.com, TryEngineering.org), high schools (neok12.com, aventalearning.com), case studies (StudyNet), and lecture notes (GradeGuru). Flat World Knowledge publishes free digital textbooks, while Chegg is a textbook rental service. InkLing is following the "iTunes for iPad-optimized digital book" model and adds social features to it. Rosetta Stone publishes interactive language courses on DVD.

4. Networks and Marketplaces







The web is an ideal tool to connect sellers and buyers in any market. Once you get a critical mass of initial users and investment in a brand, the network effect will keep you growing. The first marketplaces are already here, but the bigger fight lies ahead.

A number of sites (TeachStreet, BetterFly, School Of Everything, GuruVantage) offer tutor and training listings. TheoryAndPractice.ru is a very popular Russian language site for "edutainment" event announcements. CraftEdu.com is marketplace for paid/free online video and live training. Student Of Fortune is a marketplace for homework help. GulliverGo is a listing hub for educational travel. Noodle.org is your guide for choosing college. General purpose employment websites have sections for jobs for students and internship search. JobSpice.com helps students to create their online resume.

5. Live Training and Tutoring







As bandwidth improves, a number of startups are offering web-based live training. General purpose tools like Justin.tv, Ustream, and LiveStream can be used for streaming lectures and conferences. Supercoolschool and EduFire.com provide specialized live teaching tools. Myngle.com (languages) and TutorVista (high-school help) are tutor-student networks for live education. Sugata Mitra introduced the concept of "Granny in the Cloud" — senior volunteers who encourage kids to study using Skype video calls.

6. Learner Tools







For centuries, learning was based on classroom lectures and books. Can computers and mobile devices offer more engaging alternatives? Having a conversation with your teacher is much different when your classroom backchannel is powered by Twijector. Need to memorize something? QuizLet.com provides tools for fun flashcard-based learning. Commuting? There is a growing number of mobile learning apps including notes (StudyBlue, Widescript), law bar exam preparation (BarMax, costs $999), and driving test preparation (uHavePassed). Other tools include career orientation tests and educational games.

7. Collaborative Learning







In traditional education, being a part of a campus community can offer as much value as the lessons themselves. It is no surprise that the community aspect is moving online too. Services like UnClasses.org and OpenStudy.com allow learners to form groups and study together. Quora.com and StackExchange are modern question and answering platforms for professional topics. There isa large number of education forums such as LiveMocha (language learning) and Edublogs.org (teacher community).

8. Funding and Payments







When it comes to financial resources, there are often a lot of questions and almost no answers. How do you keep college prices under control? How do you make education affordable? How do you increase salaries for the best teachers? How do you create more competition and less governmental control in education? Sites like Enzi.org and GradeFund help students get crowdfunded loans and sell shares of their future salaries. It is a good start, but much more innovation is needed.

9. Hardware for Education







Specialized educational hardware for education can be a controversial topic. While some argue that education tech should rely on standard hardware, others see opportunity. One Laptop Per Child has produced and distributed almost 1.5 million inexpensive laptops optimized for students in developing countries. Kno is a new tablet computer hoping to be the "Kindle of textbooks." Other notable computerized classroom solutions include TimeToKnow and SOLE project.

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