I am going to say the opposite, and this is just my opinion, but I want you to think about a few things.
I was a Wilton instructor and loved it, however I had to quit because it was taking up too much of my time for too little pay. If you own a cake business the evening it takes away each week from your cake baking or your family will begin to take a toll on you.
Not only do you have to bring mixers, ingredietns and pack your car up each week but you have to get there to class early and stay late cleaning up and clock out, plus the time it takes to pack your car up and drive there, get home and unpack each week. That being said, i did love teachin students, that was the best part, and if you have no other job and no cake busniess on the side, it is an excellent part time job. BUT if you have kids, another job already plus a cake business I think you really need to think about the extra time spent away from home for the little bit of pay they provide, which in my opinion is not enough.
Now the pay from what i remember is based on students, so i fyou get 12 students or more in your class then it may be more beneficial, however if you have 3-5 you get paid way less, and you never know how its going to work out.
Just some things to think of and I wish you the best!!