If a 14 year old only had schooling for only 6-12 weeks of her whole life can she go to a public school for 2 months and can she get A's, B's and C's for having no education at all? How long would it take a 14 year old to be able to get those type of grades without an education? We are not talking about someone who is gifted.
With only 6-12 weeks of schooling, can this person read and write? If not, then I don't see how two months would be enough to teach her how to read and write and then gain enough knowledge to get A to C grades in a range of subjects.
I may have missed something in your post, but may I ask what your question has to do specifically with the English language?