We've never tried this at school, but my church did an annual parents' dinner sort of along the same theme. There was food and entertainment, but no alcohol.
One year they had an entertainer who played the piano, sang, and talked. You know - the type who can sort of take you on an amusing stroll down memory lane with favorite songs from various generations.
Another year, it featured a local marriage counselor who was an excellent speaker, and must have been a comedian at heart. His presentation (45-60 min) was insightful, thoughtful, and hysterically funny. It was called something like "The Ten Myths of Family Communications". I remember one was "There shalt be no progress on a disagreement until blame has been properly assigned."
It was a lot fun, but a LOT of work for those who put it together. Eventually the event was discontinued.
I think it's great you are willing to do this for your community, but you might want to start small and see what the interest is, or at least see if you can get RSVP's in advance.
We have had two parent nights in the last two years. The first one was a craft night, the second was a scrapbook night. Their was free child care provided as well as refreshments. We had a very poor turnout both times (three people). Parents are SO very busy that if the activity doesn't involve the family, or provide needed information(parenting classes, testing info etc.) they just don't have the time for it. They would rather spend the time they have with their kids.
One of our goals is to foster the sense of community through school activities. We have discussed the idea of having an evening activity for parents. The question is what, where. The idea of a stand up comic, hypnotist, even a magician have been talked about. The problem is it would have to be tastefully done. Also if we rented a hall, what about the alcohol question. I hope people would behave but I would hate to see headlines about a drunken brawl at the local PTO function. I did have the idea of a non- alcoholic tropical drink bar. Has anybody done this ? Suggestions? Pitfals?
