I believe STEM subjects like maths need to be taught from the bottom up - if you don't know the absolute basics, somewhere along the line you're going to get really confused even if you generally know what's going on. Eventually you'll reach a problem which doesn't make any sense - I remember when learning matrices for the first time in A-Level I had to revise some of the most basic GCSE maths notation to do with brackets (parentheses) - something I hadn't revised since year 11. Once there is a basic level of understanding established, I can work up from there, and see which learning strategies better suit each student depending on their interest. I tend to lose focus when I'm less interested in something, so my aim is to try and not make anything seem boring, with minimal impact on what I'm teaching.