As we've previously discussed, drop off age varies from community to community and from family to family. If you're expecting adults at your kid's party, don't forget that they too are your guests and need to be cared for just like your pint-sized guests.
Although everyone loves cake and ice cream, if you're having adult guests you probably want to include some diet-friendly munchies as well. If the party is going well, the kids will all be busy playing, meaning you probably need more adult food than kid food. Veggie sticks and cheese and crackers work well for both audiences. If you're having a morning party, coffee is a great idea (don't forget to keep it out of kids' reach). If you'd like help from your adult guests, make sure to ask individuals for specific help. Especially if the party is in your home, your adult guests will be reluctant to step in and do things like get drinks out of the refrigerator or start new games. They aren't being unhelpful, they're being polite.
If you're hiring entertainment, make sure to let him or her know how many adults you expect. That way the entertainer can incorporate material meant for the adults in the audience as well. Finally, don't forget to greet your guests and introduce yourself to parents you don't know. It can seem hectic and overwhelming when the party is just getting started, but try and enjoy your guests of all ages.