Tuition is NOT ????? ???? ?????? ???? (and my Rov agrees). This would include a tutor, but tuition includes many things besides Limud. Perhaps it would cover that portion of your tuition that is paid to your son’s (only a son) Rebbe proportional to the number of children in the class.
For example, if the rebbe gets paid 40K and there are 20 children in the class, then 2K of tuition is ????? ???? ?????? ???? , and the rest is not.