Once the student can display an alternative behavior (one that replaces the private behavior) under one condition, are you arranging multiple opportunities for the student to practice the skill in multiple settings?
Have you adapted visual supports so that they can remain in the natural environments that this student encounters now, and in the future?
Consider ways to make the visual supports (e.g. a behavior contract, visual reminder cues, coping cards) portable and discrete. Should each educator, and parents, have a copy of the behavior contract that he/she can present to the student?
Are you collecting data to make adjustments to your teaching and to ensure that the student is adhering to these rules, and refraining from private behaviors, across multiple public settings?
In some cases, it would be appropriate to share the data with the student as you deliver consequences indicated on the behavior plan (i.e. reinforcing consequences, or punishing consequences).