Khan Academy, a treasure trove of educational video tutorials, recently released an app for the iPad. Now you can have access to more than 2700 videos not only from your computer but also your iPad. If you are not familiar with Khan Academy, you must check it out. If you already know about Khan Academy, you must get this app. As if Sal Khan and his team had not yet established Khan Academy as a legitimate force in 21st-century education, they certainly have done so now.