R.D.
Time management and self discipline! Think of it like this: your school work and studying is your job; act like you're working from home.
I currently work from home AND I've taken online classes... it's not for everyone.
You have to dedicate certain blocks of uninterrupted time to school work... no distractions! Also, make up one place in your house solely for school... if you don't have a desk, the kitchen table works fine, as long as everything's in one place and it's not in front of the t.v.
The hardest part is pushing yourself to get things done before deadlines. Most people who fail at online classes fail because they think 'oh whatever, I can get this done after dinner'... and then it never happens. It's really easy to play hooky or get distracted.
I personally LOOOOVED taking classes online. I'd still have to go to school to take my actual exams and do lab work, but it was so great for me!! Good luck and congrats, I get excited when I hear about people going back to school! I want to get back into it myself!! :)