When I was a new parent I wanted to know what I could do to help in the school and how I could get involved and make a difference in the quality of education my children receive. Think of how you would answer someone who wants to know those things.
When I spoke at kindergarten roundups(after I got myself in deep with the PTO:)) I would tell the parents the group's mission and then speak about some of the main events we coordinate and fund. After that I would tell about all the volunteer activities and give brief descriptions of the board positions. Our roundup was always in March so I would invite the parents to attend the next three meetings for the year and invite them to our spring carnival if roundup fell before that event. We also handed out our pamphlets and a "calendar of events" for the rest of the school year and the beginning of the next school year if we had some of those things set.
I would look at your mission statement and tell them that the PTO supports your staff, teachers, parents and students. Tell about the things that you do each year and that the more people that pitch in the less there is for the others to do.
I would also encouarge working moms, like myself, I always felt encouraged to help with what I could.
