Sounds like you have "every PTO presidents nightmare" happening.
For future use- have two or more committee members count any incoming cash and record it. MAKE the treasurer give them a receipt for any funds she accepts. This is to protect all parties involved. Secondly it cost about $125 to have 5 members bonded- in this case it may have been worth its weight in gold!
Do you have a budget from last year and how far off from it are you? We have the last 6 years in front of us and the incoming funds do not vary much. This might help make your case especially if it is in EVERY account (or committee).I guess if I had to deal with this and I had that gut feeling I would include the Principal and the Board of Directors in a meeting. Then I guess take suggestions from them on your plan of action! Good Luck!

FIRST...Make sure you get ALL your facts straight!! One thing I notice you mention is that "some" people made notice of "her" making deposits into her trunk. If these people will come forward, they can support your claim as witness. Of course assuming that such depositing actions are not the norm for your organization? Everything we do involves more than 1 person handling the $$, less chance here. We have even had an officer holding the funds collected for us [ community involvement officer, he also makes count of the funds and can verify the amount if needed].
As for handling , go to your by-laws, if not in there, go by Robert's Rules...
My 02. ... You need to have your facts straight before any accusations are made or fly by word of mouth. You'll need to have an executive meeting with the party suspected. The other officers need to decide/vote wether or not there is enough grounds/evidence and move forward from there. if there are..take it to a general membership vote. You must allow her/him to have fair process at all times. Do not siderail this person, they may be innocent, which is why you get your facts together "QUIETLY" first.
GOOD LUCK..In the meantime you may look into "suspending" [or asking her/him to step aside]this person until the truth comes out whichever way it may be.

Defently let your Principal know as a sort of heads up in case things get ugly. Can you check with the bank as to what was deposited during this time? How are checks handled, the bank should (hopefully) have a record of everything that happened during that time. Talk to your volunteers, but keep it clear that you on a fact finding mission. I would defently get your 'ducks in a row' before meeting with her. In our by-laws the Principal is included in the meeting you will need to have with her. Do you know her husband well enough to talk to him? He might think it's odd they had such a great Christmas. Make sure you have all your info before saying anything. THe hardest part, you may want to ask your principal will you have his/her support if it becomes nessary to go to the police. I know. yuck. Good luck and may the force be with you! (My husband and 3 boys are huge fans!)

Help! At christmas our PTO participated in a Santa shop fundraiser. When the fundraiser ended, due to unfortunate circumstances, I, the PTO president ended up doing the final inventory. Myself and a few other mom's counted and documented the remaining items. Maybe I should say at this point, during the week the company (Santa Shop)had become overwhelmed with requests for having merchandise shipped. Our shipments were either not received or received late. In fact we received the bulk of our shipment on Friday (the last day) at noon. This really added to our nightmare. Anyway, I could not make our inventory match. I tried over the weekend, and on Monday went back to the school to recount some of the items. In order to make a long story short, several parents who worked this Santa Shop came to me with several concerns they were having. Our treasurer seemed to be making cash deposits to the trunk of her car during the day. After inventory was done I felt as if our deposits to the bank were not being reflected. You know how sometimes you just know you know. This was the feeling several board members had, plus our treasurer suddenly had money to purchase some high dollar items at Christmas. A computer being part of these purchases. Some of the board helped to come up with a plan to confiscate the check book from her. I don't believe in making accusations that may not be true. I would never want to ruin someone's life. I went home and entered our checking account information into my quicken program. It was fairly clear to anyone who has served on the PTO Board, there was a problem. On the surface, just looking at the check register, everything looked fine. It was when I printed reports of each event (expenses and income combined) I realized that any event that had cash involved, we did not make a profit. Where as in the past years we had done very well. We do not have any proof, as there is not a record of the actual amount of cash. I just know there has been questions raised. How would you handle the situation? Would you meet with the principal and explain the circumstances? Would you take a board vote and remove her from her treasurer? Would you confront her and give her the opportunity to come forward and make restituation? Of course no one knows the extent of cash taken by this person. How would ya'll handle it? Please reply soon, as I feel like the walls are closing in on me. Realizing that with every passing day someone could spill the beans. I certainly don't want it to appear as if we are covering for our treasurer.
in need of advise soon.