I attended a local community college that had what they called a Professional Golf Management Program. It was taught by PGA professionals and covered both the buiness, playing and teaching sides of the business.

If you haver the game (and the time) you could also go through the PGA program. First your game has to qualify.

Third option is the USGTF. Based out of Florida but they conduct classes all over the country. Pretty reasonable cost if you get through to their Master Teaching certification. Hope this helps.