Seriously, I just started thinking about this yesterday, and I have one on my e-mail homepage. It's just called calender, but u can send updates to your phone too I do believe. I just started mine yesterday.
Try Yahoo groups. You can have your parents sign up and post on line and you can put things in the calender and email it to all the parents that have signed up automatically. It's really neat. We did it this year and it worked out well. You can put things on there also that only you can see. You get to chose who is in the group so others outside of your organization can't post things without your approval. If you set up a PTO email with the Yahoo, it keeps things separate and it has a task list on it. It's really fun thing to do! I hope this helps!
Check out springpad... I haven't used it long, but I do like it. I have been using Google calendar for several years. I can create various calendars (Kids, work travel, birthdays, sports, PTA). they each have a color. I can access online, on my phone. I share the PTA ones with my PTA. It works great. Springpad has really nice ways to deal with ideas/brainstorming ets...
I am a big fan of using Google docs, calendar and tasks to organize my life. (You just need to get a free gmail account to use.) The nice thing is that you can share all of these with whomever you chose, so you are all on the same page.
Coincidently, I saw this free organizer software mentioned on Twitter last night: www.cozi.com/homeb.htm
I don't know any more about it, but thought it looked interesting.
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