Excerpt by David Wees
Imagine you are back in school at a track meet (which by the way don't happen anymore in a lot of schools) and you have a high jump set up. The bar for the high jump is initially set so that every student has an opportunity to jump over the bar. Students who cannot jump, for whatever reason, do not participate. Over time, the bar is raised until only a few top students manage to make it over, and eventually a tie occurs, or there is a winner of the competition declared. Every child gets to experience some level of success, although for many children this success will still be a relative success as they will naturally compare their ability.
If the high jump was like how we run standardized tests, every child would be expected to be able to jump over the same bar and labelled a failure if they don't succeed. For some children the bar would be set too low, and they would set lower expectations for themselves in the future. For other children the bar is set too high, and they will label themselves a future. Many of them would not participate in future competitions simply by dropping out of the track and field event. For some children, the entire exercise would be ridiculous because they couldn't possibly jump over. Further, we would judge schools and teachers based on their ability to make kids jump over the bar, without concern about who they are working with. As an aside, some school districts (like NYC for example) would be using a special rubber bar that they can flex to ensure that the "right" number of kids are able to pass it.