If you are private, you may actually be able to go to your school's board and get some help.
If you're public, I would guess that you're not going to get too far. You made a donation to the school to fund a "program" and the school is utilizing that money for that "program". Unless the funds came with specific stipulations on their use and what would be expected of the staff selected for those funded positions, then you are probably out of luck. Have you spoken with your principal about the parents' concerns and desire to have more say? What was his/her response?
The only way I can think of that would give you more control was if your group actually did the hiring and payroll for these positions. Not something I would want to get into as a parent group, but that would be your choice.
Traditionally our PTO has raised in excess of $60K to provide one teacher's aide per grade level. The parents (PTO) raise the money and give it to our principal to effectively use.
However, recently there has been concern from parents and faculty on how effectively the money is actually being used. What say do we actually have in the hiring, firing and job accountability of our aides?
It is "our" money, so many parents feel like there has to be better accountability.
We need suggestions on how to have more input into the effective use of our money and the TA's.