Monarch School is a San Diego-based public K-12 institution that exclusively serves homeless students. Begun by the San Diego County Office of Education as a drop-in center for homeless high school students, the 170-student school is now a public-private partnership between the San Diego school board and the nonprofit Monarch School Project. The school is one of a small number of schools across the country that specifically serve students affected by unstable housing conditions. Those schools, along with other schools nationwide, are seeing a growing number of students who are homeless. Experts say the recent recession has exacerbated youth homelessness, and schools serving this vulnerable population are now being challenged to keep up with the rising numbers of students and offer the unique services to which they are entitled under federal law. The San Diego area has been hit especially hard economically. According to the San Diego County Office of Education, there were 13,204 homeless students countywide during the 2009-2010 academic year. Monarch School has seen a 74 percent increase in enrollment in the past three years. While the school never turns away its students, the school has outgrown its current space. This summer, it will begin work on a new building in which school officials hope to serve about 350 students. The school does not recruit students--most of its families learn about it by word of mouth or through social-service referrals, usually while living in shelters. In nearby Arizona, Children First Academy, Phoenix Campus, another school serving homeless students, has seen its waiting list grow. Enrollment in this K-8 school has increased by 12 percent to 18 percent in the past three years. Because the homeless student population is transient, the school's average enrollment fluctuates between 280 and 320 students, its maximum capacity. During the 2009-2010 academic year, the school's waiting list had about 12 students. This month, it has 60 students.