He was not my school teacher, but he was my second employer(when I was 19)
"Once you have a job, do it with the same enthusiasm as if the business were yours, that
will help you to grow within that job, and also teaches you the attitude needed to start your own business" -- Javier Elizabeth.
(I started my own construction company with 5 employees by the age of 20 making over 120k/year -- that was a lot of money back then)