I would advise against going to school high because it gets habitual. I regret being high for school for the period of about two months straight where I would smoke before school every day. After a while I realized it was better to just go about the day (and rarely toke up before school if some other guys are up for it), and then after the school day is over, finally smoke. Not to mention I was building up a hell of a tolerance this way and would be pretty lethargic throughout the day. Weed has to be used in moderation. Otherwise, not only do tolerances build up, but the effect simply isn't as desireable if no anticipation is built up.