thank you all for your input. as i see it, the course would be for credit and the project would be managed by a licensed Landscape contractor with student labor as part of the course. i will be in the situation that if the idea is accepted by the college, i would be the course instructor and handle the administration, with contractor coordination. which would include all the organization of materials, donations, etc.
i believe that this experience would benefit the students in that they would have a better understanding of the function of the materials they are designing with; as well as give them a leg up on things when interning.
again, thank you all for your input. i would love to hear from you all more if there is more advice.