If you want to teach yoga, or if you want to understand what is involved in studying to become a yoga teacher, you might look at the web site of the Yoga Alliance. The Yoga Alliance does not certify teachers, but it provides a stamp of approval for programs that meet what are considered to provide a basic level of information. So if you go to a yoga studio you might see a teacher listed as RYT 200, or RYT 500, or ERYT 200 or 500, and so on. The # stands for having a certain amount of experience teaching, and the 200 or 500 (and now in some cases 300) stands for hours of an Alliance approved teacher training. I, for example, am an ERYT-500. There are tons of schools, some of which give more general training, and some of which train in a particular style (lineage), but they pretty much all need to meet Alliance standards. Some trainings are residential, you go and do the whole training at once and stay at the Ashram or school, some are done over the course of a number of evenings or weekends. It used to be harder to find a school in one’s own town outside of big cities: that is certainly not the case now.
Most of the yoga teachers I know who teach in yoga studios have more than this…. we continue to study and train not just to master the postures, but to be able to understand and lead meditation, to practice pranayama techniques, and to understand the philosophical foundations of the discipline.
However, as Nancy points out, there are plenty of classes that teach varients on the more traditional form, many of which are more strictly anatomical in nature. A lot of places prefer to offer yoga style classes, or fusion classes, or classes that are postural more than multidimensional. And there are a lot of trainings to choose from.
Here is a link to where IDEA compares various places that offer yoga ‘certifications'” http://www.ideafit.com/certifications/yoga
Keep in mind that if you want to teach where you are already teaching you might ask your coordinator what they need from you to let you have a class. If you want to teach elsewhere you should look to see what local clubs want.
Some clubs will be more open to you having a less prestigious specialty cert., as long as you have a group ex cert that is nationally recognized and NCCA accredited, but I would suggest it would be prudent if you are going to go the route of getting a club yoga training to make sure it has that NCCA accreditation. There are some other accreditations that use a gold seal, but are not the same thing, so look closely. Many of those trainings will allow you to train quickly and teach a form based class. And each one will provide you with a list of readings. It would be hard to tell you what they will require. If you were going to a yoga school there are texts you would absolutely have to read, but if you are dong postural yoga style exercise there are tons of options.
My favorite reference book for structural, physiological, and kinesthetic questions, by the way, is Mel Robin’s ‘A Physiological Handbook for Teachers of Yogasana’.