A small business of this kind is the most brutal possible introduction into the realities of economics. Most *successful* small businesses involve the sale of non-optional goods, like food. Anything more optional (even like medical insurance) and the purchase rate starts to fall. Photography is at the far end of luxury goods; anytime anybody has a small economic problem, it's stuff like photography that will be cut first (even if it's educational.) Essentially your friend would be teaching people how to do a craft that is becoming obsolete, and that would require them to spends thousands of dollars even to get involved in...IN a really big metro area like the one I live in, I'd expect you might get a half-dozen people. Once.
The way this kind of business survives is to have it as an after-hours hobby that pays for itself, but that you don't really derive any income from. A "club," running out of somebody's basement, would not be a bad model -- like a women's quilting group. But the minute you start charging, you have all kinds of other problems. Somebody falls down, or pours developer into their ear, and you'll get sued, so you need business insurance. You need a space -- who pays for it? I once had a relatively small office on a the seventh-floor of a not-very-successful downtown office building, and it cost me $30,000 a year. Who pays for phones, electricity, etc.?
All the money tied up in that stuff, just sitting there, could be in a mutual fund earning more...
What you've outlined sounds like a recipe for disaster.
OTOH...there are always successful artists around. But that's also a brutal business, and usually begins as a photograhy job that allows you to build a repuation as an artist while you're getting paid to work in the field...
JC