Robert Fulgum was delighted that a student brought an actual human brain to show and tell.  The students got to hold the three pound organ in their hands.  “I have one of those things between my ears,” he said, reminding them that not only does it serve to monitor and adjust all the functions of the body, from breathing to moods, it holds much more:   [It] contains all the limericks I know, a recipe for how to cook a turkey, the remembered smell of…