Now that you have established contact with another parent how do you know they are a safe driver? or even a decent human being?
First, the parents involved in the ride share should all have children enrolled at the school. If an adult expresses interest in becoming a driver on the blog and you cannot verify their child is enrolled in the school their interest should be suspect.
Especially in the beginning, passengers may want to be picked up at places other than their homes for safety reasons. An unscrupulous person who knows, e.g., where you live, that you live alone, and your work schedule can use that information for burglary or other nefarious purposes. It is unlikely that your personal information would be used for such purposes by other carpoolers, but you may not want to take that chance. That is why some carpooling websites such as RideshareOptimizer.com note that you may want to list your pick-up location as a public place near your home such as a school or store.
It is highly recommended that all adults participating give permission for the NZ police to complete a background check.
Sex Offender Data Base - this is an incomplete project but is all NZ has for the public.