track and field in japanese high school

i graduated from high school last year.
When i was a high school student , i belonged to a track and field team .

                                                  (i was in the track & field team).
There is a most Japanese high school sports contests that is called a interscholastic athletic meet .

(There was a sports meet called Interscholastic athletic meeting, in which most of the high schools in japan participate.)
That interscholastic athletic meet take part in is both their dream and their most of the event.

(Participating in the most events of the Interscholastic athletic meeting was their dream.) [this one 's by guessing, i m not quite sure the meaning you want to express in the last sentence, sorry....]