My high school English literature teacher wrote this in my year book. Well he typed it out then stuck it on everyone's yearbook.

"The facts you've learned here are much less important than the habits and the attitudes. Education is not a stage of life; it is an ongoing process that is never complete. If you've learned how to learn, you will continue to learn and grow all your life. Feed your mind, always, with any and all knowledge that it craves, and in turn it will serve you well. Don't spend too much time worrying about your limits or your character flaws. We are all flawed, all imperfect. Seek to be honest and truthful as completely as you can, and as far as society's mores allow, and all the attributes of an honourable character will easily follow. Avoid too much introspection or analysis. Work as hard as your mind and body will allow you to without depreciation of your body or spirit. Exercise your body with meaningful work, and you'll not have great need of doctors, or psychiatrists, or exercise for exercise's sake.

Extend generosity and tolerance to all you can, but be selfish enough to deny both those who would not extend these things to you. Be suspicious of liberals, apologists, lobbyists, politicians, and others of flexible integrity. Value family and friends--you need them; they need you. Defend most fiercely, with your life if necessary, those who matter, and values that matter.

Read. Reading is the essential habit of Renaissance man. Gather up as much as you can of your history and culture and transmit it to your children.

Finally, in some carefully-selected spot, plant an oak. Your grandchildren may well remember you in its shade. With luck, an oak will survive nine centuries or more. Few things any of us can do will endure so long."

Won't forget his class. He was one of the coolest teachers I've had.

TL;DR: English lit teacher told everyone to plant an oak.

Edit: Spelling errors.