This is a great presentation by Chris Lehman, principal of the Science Leadership Academy in Philly.  I also really like this “youtube” type service. Viddler lets you add comments directly to a video.  I see a lot of applications for the classroom.  (Note: This presentation was given at an “IgnitePhilly” event.  Participants were challenged to give a 5 minute presentation (20 slides, 15 seconds each) on a topic of their choice.)

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