One of the main cons of distance education is that not all classroom courses are available online, meaning you will have to opt for a similar class or wait until it is offered, if ever. Ryerson University, in Toronto, for example, offers over 40 history courses in the classroom, but only 10 as distances classes. Also, many subjects, such as French, math and biology, are not offered at all as distance courses. Some schools, like the University of Waterloo, only allow part-time students to take distance courses and honors students can only take core courses by distance education under exceptional circumstances. Federal law in the United States restricts the number of online courses a student can take.
While a teacher does lead a distance class, he is not as easily accessible as a classroom teacher. Most correspondence is via email or by phoning his office. The problem with this method of contact is that many students will be emailing and phoning, as well as vying for his time in person. There is a good chance that the professor will deal with people in his office before phone calls and emails, so it could take a while for you to get a useful reply.
One of the most rewarding parts of university is the campus life. Many people make their life-long friends here, either through academic or social circles. The academic circles broaden our horizons by introducing us to new ideas and ways of thinking, while the social ones introduce us to people from different walks of life. Study groups are an important ways to get input from others and push us to study more. Living away from home, either on or off-campus, teaches self-reliance and responsibility. While study groups are possible online, they do not offer the same kind of personal interaction.
Studying online requires a good Internet connection, usually high-speed Internet as dial-up is usually not fast enough and will compromise the computer's performance. For students living in a city, this may not be a problem, but for those who are in remote areas, it could cause problems. Certain courses may require you to submit assignments in specific formats, which you may not be familiar with and may require a little more time. If there are technical problems on the school's end, it could take a while to get in contact with them to have it fixed, resulting in a loss of momentum and study time.