Some time in August 2012, or earlier.
I wanted to teach my Primary 5 son some Calculus. He's not a nerd and I didn't know Calculus myself. We were doing it just to test how cool he can be in the face of some supposedly "scary" problems.
My purpose was clear: just 2 or 3 inspiring real-life problems, 2 or 3 simple formulas or procedures, just 1 or 2 hours.
I had read about how Calculus can be used to calculate optimum prices etc. I had also read about Einstein's gratitude to his childhood textbooks: simple, easy, general, introductory, user-friendly, kid-friendly, (in his hand-written translated diary, to be accurate.)
Many outsiders realize it can be beautiful and desire to see its beauty with their own eyes:
That is taken from "Calculus Made Easy" The 1998 Edition's introduction by Martin Gardner
Can you find such a book easily in our modern days? Excluding the Khan Academy or any online stuffs.