[second--shift]

everytime you wad up a piece of paper and Kobe Bryant it into the rubbish bin, you're doing differential calculus in your head. The starting velocity and trajectory of the paper wad is decided upon based on the parabola's first and second derivatives.

You may not know it, but you're definitely using the calculus "intuitively" - that's why the paper doesn't land right in front of you, or into the next room over, even if you miss the basket.