We were sort of like AnyDrinkie. We didn't flat-out say 'no kids' but they weren't included on the inviation. The only children who were explicitly invited were those belonging to my two bridesmaids (one of whom happened to be my sister-in-law.) And neither of them brought their boys.My bridesmaid from out of town was going to leave her son with her dad, but then her husband couldn't get off work, and she wasn't driving in from Austin with a 5-month-old by herself! So the baby stayed home.
We decided we weren't really going to fight kids if they showed up, but we weren't inviting them, and we spread it around that the venue was not totally kid-friendly. We had a lunch-time wedding and the reception was up a long flight of stairs... with a courtyard downstairs. No grass. No real place for kids to run and play. We just didn't want to deal with it.It might have been different had we had a venue that was more kid appropriate.
The only kids we had were a coworker of mine brought his boys, in large part because they had two weddings to go to and the second was kid friendly so they left directly from mine for the second wedding. And one of DH's cousins brought his kids, who were around 8-11 and old enough to enjoy and entertain themselves.