Why am I not retaining info from my math movie?

You’re in charge. You get to decide. Since you’re not doing this for a grade and absolutely no one is going to check up on you, I don’t think there’s anything wrong with skipping whatever you decide you want to skip.

Try getting Pi from a circle; just a plain, flat, two-dimensional circle.

Do not skip ahead to “the good stuff”; it probably won’t make any sense if you don’t grasp what came before it.

Pi is just a handy number. You already know the circumference of a circle is Pi times the diameter. It is one of the first formulas. C = Pi x D .
Do an experiment. Take a plate and put it face down on the table. Now take a string and put it tight around the outside. Straighten it out and measure the length. Now measure the diameter of the plate and multiply it by Pi. Notice anything? Bingo!

You use Pi to estimate the volume of fuel tanks, planets, basket balls and cannon balls. You use Pi to measure distance around circular tracks. The perimeter of a fence. The volume of a human head.

Oooo!!! Here is one of my favorite brain teasers. Imagine a steel band that is wrapped tightly around the Earth’s equator – (assume it is a sphere). Now cut the band and insert a 10 meter length of steel between the ends. What is the average distance the now elongated band is off the surface of the Earth? If you know how to use Pi you can figure this out in your head.

On skipping chapters: the thing about math is that each lesson, each chapter, builds on what came before. You can’t …skip a few chapters to get to the good stuff… because you won’t understand it.

If you don’t want to learn about pi and circles, you won’t get spheres, or cylinders, or lost of other things.

And the way to learn math is to watch the video, then do some exercises and problem solving so that you grasp how the concept is applied.

Good luck!

What would it take to get you interested in pi?

Would it help to measure the diameter and circumference of a circle, as @LuckyGuy suggests? What if you knew that pi is used for the volumes and surface areas of spheres and cones?

What if you knew that pi shows up in unexpected places? If you take 1/1 + ¼ + 1/9 + ... +1/n^{2 and look at the value for really large values of n you will keep approaching (pi)}2/6.

What about this mind blowing equation e^[(pi)i] = -1? In one equation you have a relationship between the two most important mathematical constants, e and pi, and two fundamental values whose existence was at one time questioned, -1 the unit for negative numbers and i, the square root of -1 and unit for imaginary numbers?

You may want to look at the book, Magic of Math by Arthur Benjamin, which should be available in your local library. It has a chapter devoted to pi.