Student enrollment at the post-secondary level is minuscule, compared with the numbers for K-12 schools, In 2006-07, about 55.3 million students attended public and private elementary schools; about 17.8 million attended degree-granting higher-education institutions, according to the National Center for Education Statistics.
Enrollment numbers at colleges and universities usually don't reveal as much as the K-12 numbers do. Steady growth in a public school system is most likely the result of real estate development that adds new homes and boosts the population. Conversely, a decline in enrollment might reflect an area where growth has peaked and residents who no longer have school-age children.
Enrollment patterns at higher-education institutions may reflect the general population trends of the community at large, but they may be the result of decisions made by individual institutions. Postsecondary institutions typically are not required to admit all students; policy decisions such as raising admission standards or increasing tuition and fees, enable colleges and universities to reduce the numbers of students who apply or are allowed to enroll on their campuses.
Still population does affect higher-education enrollment. Just like the K-12 level, the list of the largest school systems is dominated by the states of California, Texas and Florida. Together, they account for 25 of the 50 largest college campuses. California has 10, Texas has eight, and Florida has seven — including five of the top 20.
Outside those three states, the list of campuses with the largest enrollment is dominated by Big Ten Conference schools. Of the 22 institutions that had student numbers of more than 40,000 in fall 2007, eight of them are from the Big Ten.
The higher-education institution at the top of the list is the University of Phoenix. As an online operation not constrained by a physical campus, it enrolled more than 224,000 students in fall 2007.