How about approaching the administrators this way:

"I've been considering our first interactions together from the beginning of the school year and wonder if perhaps the PTO left you with the impression that we didn't want to support the school. Unfortunately, we had no choice in the decisions we made at that time as we had no budget. However, I'm happy to say that, as the year has progressed and our fundraisers have been completed, we are now able to fulfill budgetary items such as the ______________, _____________, and ________________. We've done this for 14 years, but I realize that maybe you wouldn't know this unless the PTO told you, so here I am. Can we talk further about providing the school support for these activities?"

We have a new principal and a new assistant principal this year. The principal has never been an administrator in an elementary school before and the assistant principal was demoted after one year as a principal. Ever since these two new administrators came to this school at the beginning of the year they have been combative with our parent group. We think it started because a the beginning of the school year the first three meetings we had, the principal asked for money and we had none to give so we denied her requests. I think she has held a grudge ever since then. Well, now it has come to our attention (from the teachers and staff) that she is telling teachers that the parent group refuses to support them in activities they are doing, which is not true since the parent group has always supported these activities, at least they have for the last 14 years. We can't really call her on the lies because then we would have to reveal our sources, which we can't do since we were asked not to. Any advice on dealing with administrators with no integrity?