I have a few issues with your outline:
All the parts of your outline should support the thesis.
Im not sure how part "A" fits. Whats the point of part A?
also, A, b has only "i"
since there is not "ii" there should be no "i"
b should be "comparing thai and foreign students tuition fees"
also B, a, i and ii seem very similar to B, c, i and ii
is c only concerned with scholarship students as you suggested?/?
overall I wonder what type of organizational structure you chose
is this part part whole whole
or compare contrast
or idea by idea?