Good morning, everybody.
In today's lecture, we will talk about online education.
You know, in some parts of the world, it is not that easy for people to receive education.
And even in the United States where education is available, it might not be within reach.
Thus, online courses provided by those world-famous universities can bring the best quality education to as many people as we could around the world, and for free.
First, let's talk a little bit about some of the components that go into online education.
The first component is that when you move away from the constraints of a physical classroom and design content for an online format, you can break away from, for example, the one-hour lecture format.
第一个特点就是在线教育打破了实体课堂的限制 。设计在线课程内容的时候，教师可以抛开很多限制，比如一小时的课程时长 。
You can break up the material, for example, into short, modular units of 8 to 12 minutes, and each of the short units introduces a coherent concept.
Students can deal with this material in different ways, depending on their backgrounds, their skills or their interests.
So, for example, some students might benefit from a little bit of preparatory material that other students might already have.
Other students might be interested in a particular topic that they want to pursue individually.
So this format allows students to break away from the one-size-fits-all model of education, and allows students to follow a much more personalized curriculum.
Second and perhaps one of the biggest components of our online education is that when we need to have students who practice with the material in order to really understand it.
There's been a range of studies that demonstrate the importance of this.
A study in Science last year, for example, demonstrates that even simple retrieval practice, where students are just supposed to repeat what they've already learned, gives considerably improved results on various achievement tests.
So, we need to build in much more meaningful practice questions.
Now, fortunately, technology has helped us to provide the students with feedback on those questions.
We can now grade a range of interesting types of homework online.
The third component is what is called collaborative learning.
Students could collaborate in different online courses in a variety of ways.
First of all, there was a question and answer forum, where students could pose questions, and other students could answer those questions.
And what is really amazing is that, because there were so many students, it means that even if a student posed a question at 3 o'clock in the morning, somewhere around the world there would be somebody who was awake and working on the same problem.
And he might answer that question.
And so, in many of the online courses, the median response time for a question on the question and answer forum was 22 minutes.
So in a word, if we wanted to offer top quality education to everyone around the world for free, what would that affect us?
First, it would establish education as a fundamental human right, where anyone around the world with the ability and the motivation could get the skills they need.
Second, it would enable lifelong learning.
It's a shame that for so many of us, learning stops when we finish high school or when we finish college.
By making this amazing content available, we would be able to learn something new every time we wanted, whether it's just to expand our minds or it's to change our lives.
And finally, this would make a wave of innovation possible, because amazing talent can be found everywhere.
To sum up today, we have talked about some features of online education and it's benefits.
We are sure that online education will have a promising future.
In the next lecture, we're going to learn how online education has changed people around the world.