Speaking as an educational consultant who makes her living helping families succeed in and manage the stressful private school admissions process, I try to make my clients' lives easier, not harder. Kindergarten interview/playgroup assessment and coaching is an unnecessary program. I would never offer or recommend it.
At NYC private school interviews, children often write and recognize their names, draw pictures, cut, paste, do simple addition and subtraction, listen to stories and directions, talk to teachers and peers, do puzzles, build--all tasks that children do everyday in nursery school. Children do not need playgroup tutoring.