How much of your life is spent in school?

Well, if you consider a life of about 80 years, that is 80 years * 365.25 Days/Year *24 Hours/day. You get 701280 hours in a life.

You spend about 7 hours a day in school. People who go to college generally have 17 years in school or more. (with about 180 days of school per year, give or take some) so:

7 hours/day * 180 days/year *17 years = 21420 hours

so 21420/701280 = 3.05%