For my field of study (art & photography), I think practice is just as (if not, more) essential in the learning process as lecture.
I would begin my class with lecture and theory of the subject(s) to be covered, as well as a written explanation of what they will be learning. Then, through demonstrations in lab, I would guide them through the processes that were talked about during lecture/theory. After that, I would allow them to practice what they have learned on their own.
My grading system would be based on three components---completion of body of work, critique and final exam.
The time and effort they spend in lab hours would be reflected in the quality of the work they produce at end of term (hence, completion in body of work). Weekly critiques amongst professor and peers would also be required. I would expect each student to thoroughly explain their work in concept and in knowledge of process. The final exam would be based mostly on the lecture and theory they have received.
I plan on implementing some of these assessments this fall semester for my photography course at EPCC and some as a TA in the printmaking lab.
