Many students are involved in community service in one form or another. Annual events include Dance Marathon, a thirty-hour event that raised more than a million dollars for charity in 2011; and Project Pumpkin, a Halloween celebration hosted by the Northwestern Community Development Corps (NCDC) to which more than 800 local children are invited for an afternoon of games and sweets. NCDC's work is to connect hundreds of student volunteers to some twenty volunteer sites in Evanston and Chicago throughout the year. Many students have assisted with the Special Olympics and have taken alternative spring break trips to hundreds of service sites across the United States. Northwestern students also participate in the Freshman Urban Program, a program for students interested in community service. A large and growing number of students participate in the university's Global Engagement Summer Institute (GESI), a group service-learning expedition in Asia, Africa, or Latin America, in conjunction with the Foundation for Sustainable Development. Several internationally recognized non-profit organizations have originated at Northwestern including the World Health Imaging, Informatics and Telemedicine Alliance, a spin-off from an engineering student's honors thesis.