The internet is abuzz  with the launch of TED-Ed , which puts brief, punchy and free lessons online. It joins a growing list of online resources that strive to change the way students learn. Together, these resources just might be revolutionary--but they can't incite any revolutions on their own.
TED-Ed’s mini-lessons join a teacher’s voice with often whimsical short animations that aim to bring the lessons home. None is longer than 10 minutes, and all of them so far seem pretty evocative. Compare them to the celebrated videos of the Khan Academy , which are longer and less polished but more traditionally didactic. So far, TED-Ed may give you a very memorable glimpse of the infinite , whereas Khan will show you how to solve linear equations .
TED-Ed and Khan are both in the tradition of free online universities like MITx , which puts a lot of rich course content and assessments online for all to see and use. At the very least, they’re all a boon for autodidacts. The Khan Academy videos alone have racked up hundreds of millions of views in a few short years. In the few days since they appeared on Youtube, TED-Ed videos have been viewed tens of thousands of times.
So how can these new videos become transformative? Perhaps they can help teachers “flip ” lecture and homework. That is, students watch lectures at home, and then teachers help them one-on-one with homework in class. Some experts imagine that such "flipping" could herald a complete transformation of teachers' roles. A small cadre of "star" teachers  could be beamed into classrooms across the country and be seen by thousands or even millions of students. Many more teachers could work with students on site to help them deepen their grasp of the subject matter offered by these stars.
Perhaps the new videos can help transform how we give people credentials. If a person can show that she has mastered a subject after learning about it through the Khan Academy, MITx or wherever else, shouldn't she get some formal recognition for that? More and more people are trying to conceive a system of badges  that would do just that.
Of course, no set of videos, no matter how good, can bring about such changes on their own. Teachers would need very different training and a lot of on-going support to "flip" their instruction. We need top-notch assessments and some kind of standard infrastructure to ensure that badges actually communicate skills and knowledge in a clear and reliable way.
The new class of online videos may be the start of something big. At the very least, they are putting vast stores of knowledge and ideas within reach of anyone with an internet connection. In the end, though, these videos will have to be part of a larger wave of reform. They shouldn't allow them to become the filmstrips of the 21st century.