Appreciate that you are wanting to work while already doing a full time MBA. This would be a great move and will ask for greater commitment from you. So, look at your interests as that will help you reduce your stress at work and the achievements might act as a power boost for your regular MBA class as well.
Today, there are numerous opportunities for people who are really seeking out! Listing a few of these:
Online: content dev, SEO, web development/designing, blogging, etc.
Offline: marketing/network marketing, you could start to teach and train on something you are passionate about like dance or music.
At times, there are CCDs, McDonalds, Pizza Huts, etc looking for part time employees. You could contact them too. And then go for the one that best suits you! If you have college during the day, you could also go ahead to check for an opportunity with a US staffing firm where you work during the nights. So, look at your interests and reasons for wanting a job. Try linking your job with your education and interests so that they all work in tandem to build up an excellent future for you! Hope that helps!