Also, if you haven't tried www.signupgenius.com I HIGHLY recommend it. You simply create an event, type in EXACTLY what you need and then the site e-mails parents the link where they can sign up and also sends out reminders for you. This site is also great if you are purchasing gifts for needy families (it allows everyone to sign up for the exact items you listed for each child/person). I haven't had any complaints and I have had a lot of feedback that they are getting more parent participation using this site.
I hope you all have a peaceful week and fabulous parties!! We CAN do this!!