A book of wax tablets with Greek school exercises (fourth–fifth century AD)
SCHOOLMASTER In Gal. 3:24–25 the KJV translates the Greek word paidagōgos as “schoolmaster,” referring to a function of the OT law as a custodian, guardian, or tutor to prepare a person for salvation by faith in Christ through creating an awareness of the holiness and righteousness of God and an accompanying sense of personal need. The term was used of a slave placed in charge of a boy in a wealthy Greco-Roman household whose task it was to accompany the boy to school and to guide his conduct until he came of age and took on the responsibilities of a man.
Longman, Tremper, III, Peter Enns, and Mark Strauss, eds. The Baker Illustrated Bible Dictionary 2013 : 1483–1484. Print.