John Corcoran is a retired teacher who taught high school for 17 years and all that time he couldn't read, write or spell.  Until the age of 48, John was illiterate.

By acting up in school, John was labeled as having emotional and behavioral problems so his inability to read went unnoticed.  He made it through school by cheating off of friends and managed to graduate from college with a bachelor's degree in education.

Creating an "oral and visual envrionment" in his classroom, John relied on his teacher's assistants to do board work and read necessary documentation.  He did a great job teaching, but felt ill deceiving his students.  John eventually took a leave of absence to become a real estate developer. 

At the age of 48 he decided to learn how to read and write again and began working with a 65-year-old volunteer at the Literacy Center of Carlsbad.  After a year he was able to read at a sixth-grade level.

Link to article.