Duolingo is a free language-learning website and crowdsourced text translation platform. The service is designed so that, as users progress through the lessons, they simultaneously help to translate websites and other documents. As of October 2013, the site offers Spanish (Latin American), French, German, Portuguese (Brazilian), and Italian courses for English speakers, as well as English (American) for Spanish, French, Portuguese, and Italian speakers.
Education model
Duolingo offers extensive written lessons and dictation, with less practice speaking. It has a gamified skill tree which users can progress through, and a vocabulary section where learned words can be practiced.
Users gain “skill points” as they learn a language, such as when they complete a lesson. Skills are considered “learned” when users complete all the lessons associated with the skill. Up to 13 points are awarded per lesson, with one deducted for each mistake. Users start with four “lives” on early lessons, and three on later lessons, a “life” being lost with each mistake. A user must retry the lesson if they make a mistake after all lives have been lost. Duolingo also includes a timed practice feature, where users are given 30 seconds and twenty questions and awarded a skill point and seven or ten additional seconds for each correct answer. The whole course teaches more than 2,000 words.
Duolingo uses a heavily data-driven approach to education. At each step along the way, the system measures which questions the users struggle with, and what sorts of mistakes they make. It then aggregates that data and learns from the patterns it sees.
The efficacy of Duolingo’s data-driven approach has been reviewed by an external study commissioned by the company. Conducted by professors at City University of New York and the University of South Carolina, the study estimated that 34 hours on Duolingo may yield reading and writing ability of a first-year college semester, which takes in the order of 130+ hours. The research did not measure speaking ability. It found that a majority of students dropped out after less than 2 hours of study.[9] The same study found that Rosetta Stone (software) users took between 55 and 60 hours to learn a similar amount. It did not compare to other free or inexpensive courses, such as BBC, Book2, or Before You Know It (software).
Instead of slowly adding additional languages, CEO Luis von Ahn says they plan to create tools necessary for the community to build them, with the hope that they can introduce more languages and “empower other experts and people passionate about a specific language to lead the way”. The Language Incubator was released on 9 October 2013.