Responsibilities should be spelled out clearly to the intern. The responsibilities should be included in the contract and gone over with the intern. As the internship progresses the responsibilities might change and the changes should be discussed. During the internship it is helpful to keep a journal of the experiences the intern has. Also giving a presentation of what the intern has learned during this period should be provided. 

Internships should provide opportunities in different aspects of learning in the field and give the intern the experience of working as a team. The intern should also be given the opportunity to rotate in different aspects of the company. 

Internships provide hands-on real-world experience beyond the classroom. The intern learns from individuals who have experience in the field.  Also doing and internship gives you a feel if you are a right fit for that company.