Sounds like an intervention is needed. Are the parents home when the children are acting this way? It is not reasonable that they are allowed to behave this way and it should not be tolerated. They need to know that they are affecting the quality of life of those families around them - not to mention breaking the law with their rock throwing. There was a time when everyone knew their neighbors and one could speak directly to children and ask them to tone it down or appeal to the parent in the house without fear of retaliation. Find out who your alderperson is and let them know what is going on, ask them to contact the police to pay a visit or drive by in the evenings to witness this for themselves. 3 years is a long time to watch children graduate into escalating delinquent behavior for what seems like a serious lack of parenting. The family could need help and one can only imagine if they treat each other this way, how they are treated by their parents and how they act in school?