Why don’t my numbers add up?
Free online graph paper/grid paper PDFs.
[Beginner sourdough loaf](http://www.thekitchn.com/thekitchn/baked-good/recipe-beginner-sourdough-loaf-048192)
: Recipe that focuses on getting sourdough flavor without the slow-rise sourdough technique.
: Algorithms for arithmetic.
: Regular expression generator for multiple programming languages.
: A recipe site focusing on low-cost cooking from scratch.
[An old-fashioned education](http://oldfashionededucation.com/index.html)
: A directory of free homeschool curricula, literature, and text books.
: Convert the first 10,000 digits of pi into a musical sequence based on the notes of your choice.
[How to write a spelling corrector](http://www.norvig.com/spell-correct.html)
: An explanation of the statistical language processing problem of spelling correction.
: Best use of bacon ever!
My math class is doing derivatives via basic differentiation rules after suffering through doing them “the long way” (the limit process that apparently produces many groans and bad test grades).
So Mr. Riley taught us a cute math rhyme for doing the derivative of (u/v):
> Lo-dee-hi minus hi-dee-lo,
> Over the square of what goes below.
So totally awesome.