Science has proved and continues to prove that arts-based instruction requires the highest level of cognitive ability. Using Bloom's Taxonomy as a reference, our education system today only asks students to achieve lower to mid- levels of thinking by requiring students to think at comprehensive or analysis levels. It then assesses learning through standardized tests, which can only test to mid-levels of cognitive ability.
Arts-based instruction, not only requires knowledge, and comprehension levels, but analysis, application, evaluation and then the ability to create--all six levels of cognitive ability. The ability to create is the highest form of cognitive thought.
One of the problems in education today is that scientists do not know how to study creativity because science has no way to measure it. They cannot measure it because there are no theories to create a test--although cognitive load theory is making headway--Instead, education systems get stuck with how much a student comprehends and can analyze --which results in a society that promotes lesser cognitive ability.
Most people cannot think beyond an analysis level; most people do not know how to create. This is evident in the comments posted on the internet and in reaction to proposed budget cuts for the Arts ... they haven't learned to think at a higher level where they can recognize the value of what arts-based instruction does for education in developing higher levels of cognitive ability.