keep visine in your purse, tell them your going to the library. If you take a long time you can always say you where reading or ran into a teacher/friend/co-worker/ helped the librarian put up new books/read at childrens hour. (to make up for lying about the library, I used to donate $10 a month to childrens library, trying to even out my karma) If they ask about you being high, just tell them your in a wierd mood, retaining water or your about to start your period. (period excuse usually stops all lines of questioning)