I feel that the key components to a drawing curriculum should incorporate different contour drawing and other drawing exerises to really help the students become more comfortable with their skills. The other thing that i feel is valuable for a drawing curriculum is working on perspectives and proportions. I feel that students dont really look at what they are trying to draw and their proportions look wrong and they become very discourages and they start to doubt their abilities and leave the arts and dont continue with it anymore but if they would just sit there and just study the object they would be much better off and feel like they do have ability to create art. I think the balance of naturalistic to abstract comes from how you as the teacher present both styles to your students but i think you need to start of with the naturalistic style and then move to the more abstract lessons once your students gain confidence in thier own abilities.