Teach. If you're an expert in a certain subject, see if the community, local colleges, or even the private high schools in your area are looking for a teacher in your field. If you can pick up just one night class per week, it can make a difference in your income. Though you'll need certification to be a traditional teacher most of the time, to teach part-time you may only need a master's degree and proof of your expertise.
What’s the catch? None, really. Cash back apps act as affiliates for many online merchants, which means that whenever you make a purchase through one of the apps, they get a small commission — but then, they give you a portion of that commission as “cash back”. For example, if I buy a pair of Nike shoes through the Ebates app (or website) and spend $75, Ebates may get a $10 commission but then they’ll pass $7 back to me. It’s basically a way to get sale prices on stuff that isn’t on sale!