Portland, OR -

Portland Public Schools administrators are tired of dog owners letting their pets run loose on school grounds in the evening and not picking up after them.

Spokeswoman Christine Miles says Multnomah County Animal Service will conduct leash-law stings at three schools in May and ticket violators.

KGW reports the schools being used as dog parks are Beach School, da Vinci Arts Middle School and Duniway Elementary.

School administrators say it's not only unpleasant when students step in dog droppings, it's unhealthy.