By backing in, the open car door prevents kids from running into the street/parking lot because it directs them to the curb, assuming that a curb is immediately behind the space. Parents leaving the parking space can see other drivers and kids who might be in the street or infront of the vehicle. However, if there is a lot of "park and walk" pick-up and drop-off activity that takes place at the school, there is a possible safety hazard associated with drivers backing into spaces because of the potential difficulty seeing kids that are getting into and out of cars in neighboring parking spaces. For normal on-street parking applications, back-in parking is far better, but for the shared space like a school parking lot, the advantages aren't as clear. If the spaces in question were a single row of back in parking at a school parking lot with a sidewalk behind (where there is a more clear advantage to forcing kids to the back of the vehicle), the advantage of back-in parking is more apparent, but at a larger lot with multiple bays or rows of parking, the advantages may not be greater than vehicles backing out of a typical perpendicular space into the drive aisle in a traditional lot. One city that uses back-in angle parking routinely throughout the city, including schools is Seattle, WA.