It's also the responsibility of the parents. We're making very sure that The Heiress can read and write.
I understand some kids have difficulty reading. Not all kids process information the same or at the same rate, but my experiences with kids is that by third/fourth grade they have mastered reading.
My kids didn't get anything exceptional during that age group, other than the basic language arts taught in the classroom, and some free reading at home. But, they all managed to learn it without any difficulty.
I have to give most of the credit to their school program and their teachers.