Just an FYI
I went to the National Archives of Ireland website and with the help of Jane Halloran Ryan I learned about different type of census forms, like form G for students (and there are more), In the end I searched for Martin and used his birth info and included his approx age at the time of the 1911 census as part of the search criteria. Then I waded through a bunch of records for a bunch of Martin Ryans about the correct age and I found him in the 1911 census. I found Martin listed (in a form A census record) as a teacher in a school in Westport College County Mayo, a Christian Brothers School, named after Edmund Rice , the founder of the Christian Brothers.
The record gives the county of birth. See attached.
I learned a lot through this exercise.