Every time I walk onto a soccer pitch I learned something new.
Change to: Everytime I walk onto a soccer pitch I learn something new.
Joining the varsity soccer team is my most vital achievement to date.
If you can find another word for vital, you can delete 'most' and add 'est' to the end of the word, if you get me - like 'my biggest achievement'.
It wasn't only another extracurricular activity to throw on my college application, it was my passion.
Change 'only' to 'just'
My junior year was my first year on the team.
Delete 'my'
It is like throwing a piece of meat into a starving carnivorous crowd.
You need to change 'is' to 'was' because you're speaking in the past tense
Every veteran player didn't show any respect to me or any of the new teammates.
The veteran players showed no respect to me, or any of the new players.
That same year I was given the rank of Captain.
That same year I was made captain.
Through this role I gained a firsthand experience of being a leader and it advanced my understanding of leadership.
Through this role I gained a firsthand experience of being a leader and my understanding of leadership was advanced.
Not only did joining the team further my involvement of being a leader
Not only did joining the team further my involvement in leadership (you might find a better word for leadership since you ended the last sentence with the same word)
Since I was a science major I was enveloped with hours of homework and projects.
Since I was a science major, I was enveloped with hours of homework and projects.
Coming home four hours later due to practice, tired and exhausted wasn't beneficial either.
Coming home tired and exhausted (maybe just one of these words or choose another because they essentially mean the same thing), and 4 hours late due to practice, didn't help either.
Weather it was to take an hour nap,
Whether it was taking an hour-long nap,
In essence I give thanks to the opportunity I was given when I joined the soccer team. It was a major experience that shaped me who I am today, not only as a player but as a scholar as well.
In essence, I give thanks to the opportunity I was given when I joined the soccer team. It was a major experience that shaped who I am today, not only as a player, but also as a scholar.
Good luck!