I have posted on similar threads but not this one.
Did not train in high school.
9 - 7:10 (gym class, I was chubby)
10 - 5:54 (thinner)
11 - 5:45
12 - 5:20
College - 4:31
I kept running (times below by age)
28 - 4:26
40 - 4:39
48 - 4:54 (last time I broke 5)
50 - 5:01
60 - 5:15 (out of my brain on the train)