When I see group of girls with about the same age as me smiling, looking seductively and saying "hi" to me, there is nothing of consequence to ponder coz you know that's normal for a not so handsome guy like me. Nyahaha!!! But when some high school girls walking back and forth in front of our building, smiling, staring with their innocent eyes and saying "hi" with a deep breath to me, man! Flattery? Or adulation stands out. And although the place might be teeming with other guys (older or younger) trying to get the high school girls' attention, they just disregarded them on purpose, making me more brilliant and popular by the minute.
Not here to boast but when you're waiting 1 hr and 30 minutes for a demanding professor, you can't help but smile and enjoy the hours waiting as if nothing's wasted.