Help!

Save me for the insanity of teenagers!  My supervisor had an emergency yesterday, and the oldest of my coworkers took the day off, so I spent the day with three of them.  Since the oldest is 18 and the youngest is 16 I was the only driver-which made things awkward-they tried to get me to let one of them drive so as to ease the commute.  After I objected and tried to explain why, they said that I could just take the first 'load' and they'd follow-despite my protests.  My objection would mean they did it without my consent so I wouldn't get in trouble.  Teenage logic at work.
Plus the 18 year old kept getting poked by thorny plants and that was somehow my fault-even after they deliberately grabbed the broken off branch of a long thorn bush and squeezed it in their fist.  And the fact that they didn't ask what was a plant and what needed to be pulled after they pulled it is also my fault.
Then after the 17 year old left, the other two were weeding a flower bed separate from me.  I went to dump out my bucket ad spotted them walking back towards the area-yes, there was a building in the same direction-and realized it was now too dark to finish.  So I went back to the truck we drove and put my now empty bucket in the back before driving it over to pick them up.
I then spent a good 10 minutes trying to find them because they hadn't gone back to weed, they'd gone into the building to use the restroom.  I'd parked the truck on the sidewalk(one benefit of working for the school: we can drive on the sidewalks and park there when we need to-it saves walking time) so I moved it to the parking lot while looking for them.  Yet it was once again my fault they had not communicated this to me when we'd passed earlier.
They commenced to spend the rest of the evening tuning the truck's radio station to the most obnoxious stations they could find.  Ranging from a religious bible reading/choir station ( if the speaker hadn't had a monotone I wouldn't have had a problem, but they were putting me to sleep when I was already tired-and driving) to a completely spanish one, they claimed the regular stations I listened to were bad.
It seems a lot of people have forgotten 9-11 and what it stands for.  My supervisor and the 18 year old coworker both didn't realize why the flags were at half mast that day.  The university was playing the newscasts from that day in the atrium though.
I'm going to donate blood today, as we're having a week long 'blood battle' with another university to the south of us.  This is a yearly thing, but like the block party its the first year I can participate (last year I had school, and before that I'd been at work) so we'll see how that goes.
My math teacher says I didn't get a good score on the first quiz (not that I needed them to tell me that) and reminded me that the quizzes are open book.  Sorry, but when 95% of all the quizzes and test you take are not, you tend to forget or overlook that.  Hopefully I'll do better next time.