It's amazing what you can learn when you have a great teacher.
When I was a teenager I moved to a few different schools and have had a decent number of teachers for various subjects, some of whom I can't remember names for, some are stuck in my head forever.
Those are the ones who always had time to talk me through something I didn't understand, they encouraged me to push myself and always gave guidance when I needed it.
I remember a pretty amazing maths teacher, Mr Mason, a determined German teacher, Mr Knight, and an encouraging chemistry teacher, Miss Whitaker. The three of them had a major impact on me, my education and the person I have become.
Those teachers are the ones I admire, as I'm sure, many do.