Along with Laurent Clerc and Mason Cogswell, he co-founded the first permanent institution for the education of the deaf in North America, and he became its first principal.

Gallaudet started to teach Alice what different objects were called by writing their names and drawing pictures of them with a stick in the dirt.

[a] In 1815 Dr. Cogswell, with several businessmen and clergy, asked Gallaudet to travel to Europe to study methods for teaching deaf students, especially those of the Braidwood family in Scotland.

Gallaudet found the Braidwoods unwilling to share knowledge of their oral communication method and himself financially limited.

While still in Great Britain, he met Abbé Sicard, head of the Institution Nationale des Sourds-Muets à Paris, and two of its deaf faculty members, Laurent Clerc and Jean Massieu.

Impressed with the manual method, Gallaudet studied teaching methodology under Sicard, learning sign language from Massieu and Clerc, who were both highly educated graduates of the school.

After resigning directorship of his school for the deaf in 1830, Gallaudet wrote educational and religious texts, became the chaplain to the Connecticut Retreat for the Insane in 1838, and taught in Hartford; the young Frederic Edwin Church was a notable pupil during this period.