I ride thru school zones at 15mph and always stop where required and when requested by guard.

My commute used to take me thru a school zone and I 'knew' all the guards and was quite friendly with one
One day there was a substitute and I was going my usual 15mph in center of lane and the kids were still coming toward the x-walk along the sidewalk, no one was yet waiting to cross. No cars were behind me. Suddenly the guard jumped out and held up stop sign. I could barely stop in time. Then I waited what felt like forever (probably 15sec) for the kids to assemble and begin to cross. Pissed me off the power trip the guard gave me, she stood in front of me holding stop sign to my face the entire time, not even watching kids and didn't let it down until the kids had long crossed both sides of the road.

Al