Polson Bay in the southern region of Flathead Lake lies within the boundary of the Flathead Indian Reservation and is the home to the Confederated Salish and Kootenai Tribes.
In order to find this cache you will have to decipher the gps coordinates (check cache images) that are written using Kootenai language numbers. Students attending the Polson elementary schools of Cherry Valley and Linderman learn some Kootenai language including the numbers. If you get stuck consider the hint.
You can check your answers for this puzzle on Geochecker.com.