Seeking to add more space for growth, Delaware State University will take over a large hotel and conference center in Dover for student housing and office space. DelawareOnline.com says the university board of trustees has approved a lease for a Sheraton Hotel that is about a quarter-mile north of the main campus. The university says it needs more space as officials move to boost enrollment, hold down costs and grow revenue-generating programs. The $12 million, 15-year lease with the hotel includes an option for the university to buy the property in two years.