Schoolmistres or Schoolmistress: How To spell?
The word Schoolmistres is misspelled against Schoolmistress, a noun meaning "A woman who governs and teaches a school; a female school-teacher."
Schoolmistress has double 'ss' in the end mispronounced as 's'Remember double 'SS' appears in the end of this word which should not be misspelled with single 'S'
Wrong Spelling:  schoolmistre-s  Correct Spelling:  schoolmistre-ss 
Find more incorrect spellings of Schoolmistress to spell right way.