First Lady Dolley Madison and Abraham Lincoln's Secretary of State William H. Seward, who was stabbed by an intruder in his Lafayette Square house on the evening of President Lincoln's assassination. Located next to the square and on Pennsylvania Avenue across from the White House is the Blair House, which serves as the primary state guest house for the U.S. president. The United States National Arboretum is a dense arboretum in Northeast D.C. filled with gardens and trails. Its most notable landmark is the National Capitol Columns monument. A smaller urban park located in the city's limits is Theodore Roosevelt Island. This is an island in the Potomac River named in honor of President Theodore Roosevelt. The island has many trails used by walkers and runners, as well as a statue and memorial in honor of Theodore Roosevelt. Other parks, gardens, squares, and circles include Dumbarton Oaks, Meridian Hill Park, the Yards, Anacostia Park, Lincoln Park, Kenilworth Park and Aquatic Gardens, Franklin Square, Washington Circle, Dupont Circle, McPherson Square, Farragut Square, and the Chesapeake and Ohio Canal National Historical Park. Education District of Columbia Public Schools (DCPS), the sole public school district in the city, operates the city's 123 public schools. The number of students in DCPS steadily decreased for 39 years until 2009. In the 2010–11 school year, 46,191 students were enrolled in the public school system. DCPS has one of the highest-cost, yet lowest-performing school systems in the country, in terms of both infrastructure and student achievement. Mayor Adrian Fenty's administration made sweeping changes to the system by closing schools, replacing teachers, firing principals, and using private education firms to aid curriculum development. The District of Columbia Public Charter School Board monitors the 52 public charter schools in the city. Due to the perceived problems with the traditional public school system, enrollment in public charter schools had by 2007 steadily increased. As of 2010, D.C., charter schools had a total enrollment of about 32,000, a 9% increase from the prior year. The district is also home to 92 private schools, which enrolled approximately 18,000 students in 2008. Higher education Private universities include American University (AU), the Catholic University of America (CUA), Gallaudet University, George Washington University (GWU), Georgetown University (GU), Howard University (HU), the Johns Hopkins University Paul H. Nitze School of Advanced International Studies (SAIS), and Trinity Washington University. The Corcoran College of Art and Design, the