"If you haven't done anything wrong, you have nothing to fear".
This is exactly what the 5th amendment is supposed to prevent.
When the Constitution was written there was no such thing as a school crossing guard.
For that matter, there were no public schools, either. I think we could resolve a lot of these issues by simply expecting our citizens to grow the hell up and stop relying on the government to educate them, help them cross the street, etc.