Instead, let me give you an example. At my kids schools, every year they were given work books. These are books designed to be cut up, torn apart, written on, and other-wise physically manipulated, which allow children to engage with the material physically as well as mentally. This improves student understanding and outcomes. However, work books are expensive. Not all school systems can afford to give each child two or three such books every year as a supplement to the text. Further, because you always have to buy the latest work book, you have to have the latest text to accompany it. Not all school systems can afford to replace their texts at this rate. Since the work books are used two-three times per week, they have a long-term, incremental, building effect on child learning.
I can pull out another five or six additional teaching methods that are much more accessible to middle-class children, if you like.