The Academy of Orton-Gillingham, originally named “The Orton Society”, certifies individuals who have taken a training program with an OGA Fellow and who have completed a supervised practicum.
[1] In 1935, Gillingham, with her long-time collaborator Bessie Stillman, published the Gillingham–Stillman manual, Remedial Training for Children with Specific Disability in Reading, Spelling and Penmanship.
"[3] According to Rose and Zirkel, O-G programs typically "use a multisensory approach to teach basic concepts of spelling, writing, and reading and continually build upon mastered skills."
[5] The Florida Center for Reading Research reported in 2006 that it was unable to identify any empirical studies examining the efficacy of the approach specifically as described in Orton-Gillingham training materials.
Despite these conclusions, the article does provide a detailed overview of the available research, which viewed most favorably would show some evidence of benefit from classroom use of OG methods with first graders, and use in special education or resource room settings with older children with learning disabilities.