The intensity of the immersion experience coupled with the amount of exposure to the foreign language assures that students have the necessary language skills to deal with the curriculum in the upper elementary grades. Total immersion, however, is not for everyone. Not all parents or school personnel buy into the concept that students can learn just as much in a foreign language as in their own. Total immersion also requires a teacher for each immersion class. Not only are immersion teachers difficult to find, they may end up displacing staff because most elementary schools do not already have qualified immersion teachers on board.
Partial immersion is easier to staff, and the potential effect on current staff is lessened.
It is a more viable alternative for parents who feel uncomfortable with the idea of their children learning to read in a language other than English and seems to be more palatable to a wider range of parents and school personnel. Unfortunately, it is not nearly as effective as total immersion. Students do not develop the same level of foreign language proficiency as students in total immersion. A consequence of this is that students may have greater difficulty dealing with the school curriculum in subjects characterized by verbal abstractions. In the long run, partial immersion does not produce better English language achievement than total immersion.