[1] Kaplan initially embarked on a business career as co-owner of a kosher restaurant in the Chicago area.
[3] In 1987 he switched tracks and became a teacher of Talmud at Ohr Somayach, Jerusalem,[4][5] where he currently serves as senior lecturer.
[6] Kaplan launched his writing career with a 64-page "guidebook" for entry-level Talmud students titled The Ohr Somayach Gemara Companion (2000).
[4] In 2003 he compiled a humorous collection of short stories from his work with baalei teshuva at Ohr Somayach titled The Kiruv Files.
[4] Kaplan began writing a parenting column for Hamodia magazine in the 2000s and collected many of his popular columns into the books Polishing Diamonds: Bringing out the sparkle in our children (2005) and Perfecting Diamonds: Bringing out the sparkle in our children (2008).