As a stay at home/ homeschooling families we have been involved in many "playdates" from MOPS to church group to homeschooling field trips/ co-ops. We encounter so many different moms, kids, dads, and families in these groups. They are a great way to socialize, relax, learn new things, and meet new people. However we've all been in groups or situations that make us uncomfortable. I think that the type of group you are in or meeting with would determine the rules.
If I was writing a set of etiquette rules for hanging with me & my kids it would include:
* No foul language or unsavory conversations. I hate that I'd even have to include that but I am AMAZED at some of the things I've heard in the presence of kids.
* Dress yourself & your children modestly. Again should go without saying but it doesn't. It gets hot in the south but if you can't wear a bra under your tank top, put on a tshirt & a bra! Also speaking of modesty.......
* Breastfeeding isn't appropriate in front of children that aren't your own. Now I know I will step on some toes here but hear me out. I breastfed my kids but I didn't do it in public or in front of other kids. Another Social Moms contributer said it like "unless the playdate was all La Leche League members, do NOT breastfeed in front of the other mothers or children." And I will agree with her. If it's all babies and the other moms are comfortable, okay go ahead but when you have older children, they really don't need to be exposed to it. It makes them uncomfortable. Most places have a quiet area or corner where you could go to be alone to feed your baby. I took my babies to the car if we were in a public place that didn't have a quiet area. I could turn on the heat or air and the radio and be all modest and they could have a quiet meal.
* And still speaking of modesty, it's best to change your children's diaper away from the view of older children. We have a boy and a girl so they have a good idea of the difference in the sexes but families of all boys or all girls, haven't usually approached that yet. It's best to go to the restroom. Plus that gets your little one in the habit of modesty!
* Take care of your own children unless you specifically ask another parent to keep an eye on them. Now that my kids are older, I'm a little more lax with this one, but I shouldn't be! You should always (even with your spouse) bring attention to the fact that you are walking away or are distracted. This is so important for your children's safety! Simply let another adult know to have eyes and ears on your little one before you take a phone call or a bathroom break.
* Bring snacks, drinks, etc for your kids. Again one I tend to be lax about but I really try not too! If you are going on any outing with your kids, you should have snacks and drinks for them. A water bottle goes a long way. It's guaranteed that kids are going to get hungry while they are playing. Bring some snacks or keep some in the car. It makes it easier on everyone!
These are just a few of the rules I'd post if I was the playground monitor! I'm sure there are tons more that could be added! It would be great to have rules about playground bullies, certain off limits "words" for the kids, etc.