This shit is so stupid. My school actually allowed or was very lenient when kids wanted to skate out in the parking lots or do the 4 block of stairs that was pretty big, now I am not sure if the 4 block was allowed but kids still did them; just no skating in the school. middle school you would get your board taken if you stepped foot on it anywhere on the property.
Explain that skating is a good healthy, and green source of traspotation, akin to a scooter or bicycle and the school should be encouraging kids to be active instead of taking away the right to bring a board to school. I used to go to the skate park after school only because I brought my board. If I wasn't able to bring my board it wasn't really worth it to me to go to the park later after getting home.