My perfect week is when I have a day or two at each level.
If I'm at one level too long this is what happens - I play bad cop at the high school all day and don't really teach (because most the teachers think that I obviously couldn't handle high school work - being just a lowly sub and all - sigh). At the elementary I work all day long changing activities every 20 - 30 minutes - without time to pee I swear! I love the middle school but there is just so much sarcasm and hormones one can take!
So when I mix up all three I only see the good at all the different schools - High school - usually time to read or relax a bit - elementary - everyone loves me there - middle school - I can be smelly and rude along with them (very fun!)
For me its all about balance - oh and yes I try to put elementary early in the week when I'm well rested - by the end of the week everyone gets cranky and cries a lot

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