It always happens in SMK Section 9, Shah Alam. The road is going uphill, a 2 lane going up and 2 more going down which at the end is a really tight U-Turn to go back down. We have 2 gates, bottom and top and from my observation, most parents park their cars on the side of the road from the bottom gate known as gate B to the front of gate A. It really is frustrating because the left lane cannot be used as it's been blocked by the parents especially in gate B where parents just double park there not to quickly pick-up their children, but wait there for almost more than 10 minutes! Even worse, the teachers who are making their way out of school always got blocked by some irresponsible parents who stop their cars in front of the gate which causes quite a big traffic jam in the school and oitside of the school. In Friday, the traffic jam can go down to the intersection in front of the Concorde Hotel.
The other side of the road is the same too, but that one all both side of the road got car parking and you have to drive in the middle of the lines on the road which is seriously dangerous. Further addition, these cars sometimes blocked the other drivers view of the childrens who are intending to cross the road. To make the matter even worst, our school compound is shared with both Elementary and Secondary school. Just imagine...
About the exhaust emission, I have no comment for that. My understanding, I cannot blame too much for the parents to not park away from the school because simply, there's no empty parking space at all except for the one near gate C (very-very far at the back - around 500m of walking) which is not convinient at all.