Timothy Taylor observes that research about online instruction tells us that online teaching is just as effective as classroom teaching. The main drawback of asynchronous online teaching is the high drop-out rate.

He moves on to ask three important questions about e-learning for college students. Since I have been teaching computer science online for nearly ten years, I decided to have a go at his questions.

**How to deal with cheating?**

A common fear is that online students will cheat. Sure they will!

How do you fix this problem? My favorite approach is *public testing.* For example, I often ask students to post their answers where other students can see it.

Naturally, this forces you to *have open-ended questions.* My students are often surprised to find open-ended questions about, say, database queries. They expect all questions to have a one true answer. I think that forcing them to face more realistic questions where there can be many possible good answers is good pedagogically anyhow.

At first, it sounds strange: how can you evaluate the students if they have free access to everyone’s answer?

Let me consider an programming course. You could ask the students to program a videogame for their mobile phone, and to post the game together with the code on a public forum. Or you could ask students to pick an open source project and to review the source code.

In a more advanced course, you can ask students to run an experiment of their choosing and to report on the results.

How do you know that the student actually did the work? You do not know, in theory. But, in practice, it makes cheating much harder. Cheaters do not like transparency.

And, by the way, how do we know that professor Taylor wrote his own PhD thesis?

**What about students who are uncomfortable or unprepared for e-learning?**

No matter how we proceed, some students will be poorly served. This is true with classroom instruction as well as with online instruction. But there is no reason to believe that online instruction discriminates more than classroom instruction.

**Does e-learning save money?**

Classroom instruction is cheap when you can just about fill the class. However, if you have very few students, or very many students, online instruction is cheaper.

It is cheaper when you have very few students because the teacher can just point to an online site and tell the students to run through it instead of having to lecture in front of an empty class. It is cheaper when you have many students because you avoid the cost of duplicated lectures.