I was a math teacher for almost ten years and I taught a new 10th grade every year. Every year I was amazed at how many of the kids didn’t understand the basic principles of calculating percentages and geometry. Many of the kids who struggled were able to say that “one percent is one out of a hundred”, but they couldn’t take it any further than that and consequently suffered defeat over and over again. Was it because they were just unable to understand it? I don’t think so. I think that school had neglected teaching them to understand what math is. What do you see (and do not see) when you look at the world through that lens. The kids had not been taught the language of math. The big breakthroughs came when a student all of a sudden fully understood a concept like percentages and was then able to solve a problem in a number of different ways.