All you elementary school teachers out there will understand me when I say how hard it is to throw away the handmade birthday cards, the valentines, the glue-crusted, glittery pictures and the first handwritten letters that a kid ever scrawled onto paper.  (Parents too can probably identify.)  My reluctance to get rid of reminders like these has resulted in my bedroom becoming overrun with mementos, photos, knickknacks and snippets.  Every couple years or so, I reassess the importance of the tiny keepsakes that are sprinkling my room.  Some of the …