In the College of Business, our night classes are usually one day a week from 6:00pm to 8:50pm. Some professors use the full time, and others will let us out early, it really depends on their preference. It essentially takes the material learned from the two-day-a-week classes and combines it all into one session.

I personally try to avoid this format whenever possible, as I learn much more effectively in bite-sized chunks.

It also depends on what the subject it is. For example, I have two choices for ACG 3141: Intermediate Accounting 2 (Option 1: TuTh 10:30-11:50 AM OR Option 2: Tu 6:00-8:50 PM). I went with the first option because as much as I love accounting, I know that the last half of that class is going to be really tough to sit through, and it won't be nearly as productive as splitting the lecture into two.

If you have a lab where you are working with people hands-on though, it might be worth it because time will fly by so fast you won't even realize it was three hours!

I definitely feel you for the gas situation. But your education should always come first. If you think you can handle the night class, then go for it - but I would side against it unless it's a really hands-on class.