Simplify the following text for a Grade 14 native English-speaking person.
Original: Ultimately his farming proved unsuccessful and he returned to the field of education as an English teacher at New Hampshire 's Pinkerton Academy from 1906 to 1911 , then at the New Hampshire Normal School ( now Plymouth State University ) in Plymouth , New Hampshire .
Simplified: His farming was unsuccessful and he returned to education as an English teacher at New Hampshire 's Pinkerton Academy from 1906 to 1911 , then at the New Hampshire Normal School ( now Plymouth State University ) in Plymouth , New Hampshire .