Online classes are a great higher education option for people with sticky schedules. I recently had a student who worked in law enforcement at a level that sometimes things would happen that would prevent him from attending a face-to-face class regularly. While we were able to work things out over the semester, his work situation makes him better suited to take online classes whenever possible.
The major plus to an online class is that you can complete the work without attending a regularly-scheduled face-to-face class. In order to succeed in online classes, here are some things to consider.
You need as close to bombproof internet access as possible. You also need a backup plan or two for internet access in case yours fails. Even though online classes don't have face-to-face meetings, they still have deadlines that must be met.
You need very strong self-motivation and self-discipline. When you are taking a class that does not meet face-to-face, the temptation to procrastinate is much stronger. You can help prevent this by scheduling a regular time to do the work for your online class and sticking to it and by keeping up with or ahead of the readings and activities for the class.
Don't assume that your online class will be easier than the face-to-face version. In fact, the opposite is often true. A common component of online classes is participation in a discussion board with the instructor and other students. This can be quite time consuming on top of all the other regular assignments you need to complete for the class.
Most importantly, communicate promptly with the instructor at the first sign of confusion with the materials or problems with the course delivery system. It is very easy to fall behind.