In suburban Detroit, there's a speed limit sign telling drivers to slow down to 25 mph on school days.
If you're morning commute takes you past a school, you've probably seen this kind of thing.
But there's a big difference.
The Michigan sign includes six sets of times the rule applies:
6:49 to 7:15
7:52 to 8:22
8:37 to 9:07
And on... and on...
The AP says that a frustrated driver complained, making the point that to actually read the sign, you'd need to come to a stop.