Pat Sutton had it right: The principal and vice principal are the ones who can stop this -- but they may not be willing to. They could reply to each and every email your VP sends them, copying you and the rest of the board, and saying something like, "We'll be glad to listen when the PTO Board presents ideas." If the VP's tactics stop working, she might stop.
You could also simply refuse to act on her suggestions, even after the principal and vice principal have approved them. Done artfully, this could turn the embarrassment back on your VP; that's not the goal, but if her actions start making *her* look bad instead of making *you* look bad, she'll stop. For example, you say the VP sends group emails asking for a vote; do your bylaws allow email voting? If not, simply announce at the next meeting that the "vote" on such-and-such an issue was not taken legally and invite a motion on the subject; then discuss it and vote on it in the meeting, and act on *that* vote, not the email vote. Similarly, when she tries an end run and you get an email from the vice principal asking about a proposal you had already rejected, apologize to the vice principal (with your VP copied in) and say you'll get back to the vice principal with a consensus.
Be careful, though: Could part of the trouble here be that you're rejecting her ideas yourself without presenting them to the full board? You say you told her "no" on an idea, but that's not your job as president; I can imagine her complaining that her president never lets her ideas see the light of day. If there's any hint of truth in that, perhaps you can win her over by responding to her ideas enthusiastically: "That's an interesting idea! Would you bring it up at the next meeting, please? Let's see what everybody else thinks about it!" (You might have to hold your nose while you say this, but it could work wonders. And you never know; one or two of her ideas might turn out to be pretty good.)
Thanks, I'm really trying! Her main problem is that she's mad that she's not my co president. She got very confrontational on a group message with the other board members because i sent out a letter she didn't look at first. Our job duties are clearly defined, hers is to help me with whatever I need. We aren't Co decision makers on every tinny detail. If its a money our big issue our a position specific issue we discuss it and vote if necessary. But she refuses to respect protocol and I literally have the other four members trying to figure out ways to get her to step down. I've explained to her again last might why she needs to follow procedure, and her response was that she still expects me to run things by her before making Abby decisions...agree inane. Then age still didn't get it and said we'll tag team this and run this PTO . I cannot get her to understand that add VP she's there to assist not cause drama. She's the only member who fights everything I say, do or vote on...help!
THEIR SHOULD BE A DISCRIPTION OF DUTIES FOR EACH OFFICER, AND PRINCIPAL IS AWARE AS SHE IS THE PERSON ALL SCHOOL STUFF GOES THROUGH FIRST, YOU SHOULD BE RESPECTED IN THE SAME MANNER. ASK HER TO REFER BACK TO YOU, THAT WILL STOP HER IF SHE IS TOLD BY THE PRINCIPAL I NEED TO HEAR FROM THE PRESIDENT.
Do you ever have executive board meetings? If so, put "communications'' at top of the agenda for your next meeting. Rather than call her out directly (which doesn't seem to work), keep it general and say you, as the president, wanted to do a check-in on how communications between board members and board members/administration are going. Ask the group: What's working/what isn't? In this context, reiterate how the board must communicate with the administration. You are absolutely right it makes the parent group look like it doesn't know what it is doing if emails are being sent independently.
If this doesn't work, go the the principal and vice principal. Discuss the problem you are having and ask for their help in resolving the problem.
MY VP refuses to follow pto protocol and instead runs everything by the vice principal first instead of me and then issues a group email asking for a vote ...I either hear about things when the vice principal forwards me emails from her or in a group message with the rest of the board! I have told her numerous times that pto business needs to go through the pto before the principal. I have also asked to be notified of things before the vice principal to no avail. The other board members aren't happy with her to the pint that they don't want to even work with her. Last month I was sick and told her no on an idea she proposed because I'd already spoken to our accountant and was going on that advice..she then types up the proposal and goes straight to the vice principal who in turn emailed me at 8pm asking about it. I'm extremely frustrated to be put in this position, it makes the board look disjointed to have her running to the vice principal over every minute detail or idea she has. I really dislike getting forwarded emails because she runs things by everyone else first. She knows and I and other board members have tasked to her about it and it hasn't worked yet. Due to this my board members are divided no one wants to work with her ! Help