In this section, Professor Ketterle discusses how he uses a tablet computer during lectures.
I use a tablet computer, as opposed to a blackboard, to communicate my notes during lectures. I find this medium works very well.
I try to use the tablet in the same way I would use a blackboard: to write things down step-by-step as I explain them. I want to use the tablet to document what is discussed in class; I do not want to use the computer to overwhelm students with rapid-fire slide presentations or to cover more material. That is very important to me.
There are some advantages and disadvantages of using a tablet. With a tablet, you have less space on the screen, so you can write something, but then you have to scroll down, whereas in a large lecture hall, you may have multiple blackboards and, as a result, there may be more of the lecture visible to students. So that’s one advantage of using a blackboard.
However, with a tablet, I can scroll back and forth. At the end of a typical lecture, I probably would have erased the blackboards at least twice. If I want to remind students of a particular point, and that point has been erased, its visual impact is lost. A tablet allows me to easily return to text I composed at the beginning of the lecture.
Also, when I begin a lecture, I often use the tablet write-up from the previous class to summarize where we ended the class before diving into the new material. I would never have an un-erased blackboard from the previous lecture in a classroom! So, for me, this is a major advantage of using a tablet.
A tablet also allows me to post the notes immediately after class. Students understand that they do not need to copy from the board because everything I write down during the lecture is available to the students the same afternoon.
One advantage of the blackboard, in terms of addressing the class, is that I stand while I’m writing on it. I walk around. I’m more engaged. However, when you write on a blackboard, your back is to the students. With the tablet, I’m sitting most of the time (which is a minus), but I’m facing the class. I’m very deliberate when using the tablet; after I write something, I stand up to explain the concepts. I walk around the classroom, using a pointer to point to the equation I’ve written down.
Finally, the tablet has the advantage of allowing me to show how phenomena I derive have been observed in the laboratory. With a few clicks I can paste a figure from an original publication into the lecture transcript.
Although I don’t want to use the tablet to speed things up, I do sometimes make a judgment call. If I feel a derivation has too many steps and is too lengthy, and the graduate students—who are quite experienced and have already seen a lot of derivations in the undergraduate courses—would better understand it if they worked the problem at home, then I sometimes use a pre-written slide featuring the whole derivation. Instead of spending time writing down the derivation, I point out its simple mathematical transformations. In this way, using pre-written slides allows me to show students many equations without going into details.
All in all, using the tablet has been a positive experience. Students seem to like it, as well. I sometimes ask students—especially at the beginning of the course—if they would prefer the tablet or the blackboard—and the majority want me to continue using the tablet.