You can call the non-emergency number for the police and report what happened and hwere. They will know what officers are on patrol in that area, and they will also be aware of local and state laws regarding school crosswalks.
Just to give you an idea of the differences that I know about. Local elementar school has crossing guards, and people are supposed to cross ONLY with a guard's assistance if one is present (usually from about half an hour before school begins until a few minutes after it begins, and again a few minutes before school lets out for the day until about 30 minutes after it is over. There is a sign that says to yeld to people in the crosswalk. My son's high school does not have any official school crosswalks, but there are crosswalks at the intersections. There are signal lights present, and pedestrians are to cross only when the WALK light is on.
A school crosswalk near where my older son went to high school (there is an elementary school nearby) that is valid as a crosswalk only when sign lights are flashing.
Schools near my parents have crosswalks tht are only effective during certain hours of school days. In these later two examples, there are signs that specifically state how the crosswalk is to be treated.