Looking for pictures of residents of boulder school for feeble minded.

Boulder MT is in Jeffersn County MT not Pondera County. Perhaps someone in Jeffeson County can help you with this.
AT one time Jefferson County had a web site. I believe it was a genealogy site. Perhaps it is up and running now. I have not been on it for a long time
In a book I have states that the State schools for the deaf, blind and feebleminded were established in 1892. Also the town of Boulder was established in the 1860's - but the name was Boulder Valley. The name was changed in 1897 to Boulder.
Good Luck
Linda