This is not a tip for substitute teaching in the classroom. This is a tip for when you first arrive at the school. Sometimes you will get a parking stall number, other times you will see that there is abundance of visitor parking and both of these are very tempting. You get to park your car nice and close to the school in the safety of the parking lot where surely no harm can come to your car.
But I park in neither of those spots*.
You see the thing about the school parking lot is that at the end of the day it gets more congested than a nose during cold and flu season. I've actually sat in my car a good 20 minutes at the end of the day because I couldn't back out of my space to exit the parking lot because of all the extra cars picking up their lovely children at the end of the day.
If you refuse to park your precious, precious car on the street (or maybe you can't because there is parking restrictions of the street) then I suggest doing the pull through method or backing into your spot. This way you do not have to reverse out of your spot at the end of the day and can be a little more aggressive about getting the nose of your car out into the flow of things instead of making a 37 point turn to get yourself backed out and into the flow.
* ok, I do occasionally park in those spots. If it is -30°C (or -50°C) then I'll park in the parking lot so that I'm able to plug in my car and don't have to run outside at lunch time and sit in my car for 10 minutes in the ice cold to run it.