Which aesthetic theory do art teachers at school grade their students?

There is no one specific aesthetic theory that art teachers at school use to grade their students. Different teachers may have different approaches to grading, and they may use a variety of criteria to assess student work. Some common criteria that art teachers may use include:

* Technical skills: This may include things like the student's ability to draw, paint, or sculpt with precision and accuracy.

* Creativity: This may include the student's ability to come up with original and interesting ideas, and to express themselves in a unique way.

* Composition: This may include the student's ability to arrange the elements of their artwork in a visually pleasing way, and to create a sense of balance and harmony.

* Concept: This may include the student's ability to communicate a clear and meaningful idea or message through their artwork.

* Effort: This may include the student's willingness to put in time and effort into their work, and to make revisions and improvements as needed.

It's important to note that these are just a few examples of criteria that art teachers may use, and different teachers may place different emphasis on different criteria. Ultimately, the grading process is subjective and based on the individual teacher's judgment and expertise.