The MA in TESOL (TESL) is a SERIES of courses in teaching. The first part is a core course of English phonology, morphology, syntax, grammar, and maybe tranformational grammar (sentence diagramming).
Then they make you take a series of courses to see how well you can teach the above subjects, with a few courses in teaching methodology thrown in (descriptive or prescriptive grammar?) (TPR or silent method?) content based or performance based?
Then they make you write a MA thesis (or a comprehensive exam if you're lucky).
What makes you want to get a degree in an expensive place like the UK?