Hi Meggan,
Sorry there's tension with the principal. It's a stressful time of year. Maybe there's a chance to have a sit-down after the holidays. But, in terms of offsite events, if your group is set up as an independent PTO (not a school-based group), it should be able to hold events at other locations. Also check to see if your group has insurance and if there would be any issues for holding the event at a particular location.
Sorry if this has been asked before, I'm new to this site. We are experiencing problems with our current principal and wonder if our events, specifically the mother/son social or father/daughter dance have to be held on school grounds? Or are we allowed as a PTO to take them to a location off school grounds?