Because teachers are either to darned lazy or ignorant to teach them the correct way. That includes graphing.
My son was told he had to have a graphing calculator for his Trigonometry and Calculus classes. The teachers never taught them how to graph the equations. I had to sit down at home and show my son how to graph it on paper. He told me he understood the subjects better by using graph paper than letting the calculator do the work for him.
He is now in Engineering school.
Went to college for civil engineering. Even though calculators were available, we had to use a slide rule. The object was to use your brains first and then the machine. To clarify, he wanted us to know an approximate answer before we did any machine manipulating. The machine really amounted to a check on our brain work. The method was awesome.
Good for you! It’s amazing how bad public schools have become.
There is a word for this: “Afterschooling”! And...I bet the school was more than happy to take full credit for your hard work and that of your son.
The **only** academically successful children I have ever met were either homeschooled or **afterschooled**. In fact, when I quizzed these kids and their parents I found that there was NO DIFFERENCE in the home habits and **at the kitchen table** time spent by either the home or institutionally schooled children.
So?...If both the acacdemically successful homeschoolers and institutionalized children are spend the SAME AMOUNT OF TIME **IN THE HOME** doing school stuff, then maybe we are spending $17,000/per child on a government program that is completely doing NOTHING! Maybe all that academic success is entirely due to the work done IN THE HOME by the child and parents.