This month I think you oughta know about VolunteerSpot. I have a fabulous group of techified parents this year, and use VolunteerSpot to organize Friday afternoon help.
Creating a free account is easy. Simply click on create new sign up when you're ready to begin.
Customize the sign up to best fit your needs. I need Friday afternoon help, so I always choose multiple days. I choose not to have participants see who else has signed up.
Enter your information and what information you want from parents.
Now you're ready to create dates and times.
You're able to add new "spots" to whatever dates you choose.
At this stage, you're now ready to invite participants in a variety of ways.
I've always preferred a shareable link that can be sent in an email.
Another great feature of Volunteer Spot is choosing what updates you receive and how often. Participants can get a reminder email when it's close to their volunteer sign up date.