The first time I notice when I walked in the campus of Virginia Tech was the diversity of the student body.
This should be: The first think I noticed when I toured the campus....
This is an ok essay. To make it stronger, you should fully discuss what the hands on experience that freshmen at this school have. Also, since you are very concerned with diversity, you might want to add a quick blurb about any clubs/organizations that help make the transition to American college life easier for international students. - Admissions Advice Online