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  Ebah

  http://www.ebah.com.br

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  Quizlet

  We make simple learning tools that let you study anything, for free.
  http://www.quizlet.com

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  Lumosity

  Challenge your brain with games designed by neuroscientists to exercise memory and attention. Customize your personalized brain training program today.
  http://www.lumosity.com

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  TeacherTube

  A free community for sharing instructional videos and content for teachers and students. We are an education focused, safe venue for teachers, schools, and h...
  http://www.teachertube.com