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Condition of America's Public School Facilities: 1999
NCES: 2000032
June 2000

Overcrowding

Overcrowding occurs when the number of students enrolled in the school is larger than the number of students the school is designed to accommodate. When overcrowding occurs, it may contribute to the wear and tear on schools. This chapter provides information about the extent of overcrowding in public schools and the relationship between overcrowding and school condition. Information is also provided about schools' uses of various scheduling and space practices that are sometimes used to reduce overcrowding within the school.

Extent of Overcrowding

One estimate of overcrowding is the degree to which school enrollments exceed the number of students the school is designed to accommodate. 40 The survey asked for the number of students enrolled in the school and the number of students the school was designed to serve, excluding space provided by portables and other temporary instructional space. 41 Using these two numbers, a proportion was calculated indicating the degree to which enrollment exceeds the capacity of the permanent buildings and instructional space using the following formula: X= [(total student enrollment) - (capacity of permanent instructional buildings and space)] / (capacity of permanent instructional buildings and space).

Using this formula, schools with enrollments within 5 percent of the capacity of the permanent instructional buildings and space were considered neither under enrolled nor overcrowded. 42 When the value of the proportion was greater than 5 percent and negative, student enrollment was considered less than the building's capacity, and the school was considered under enrolled. When the value of the proportion was over 5 percent and positive, the enrollment exceeded the building's capacity, and the school was considered overcrowded (or overenrolled). The degree of under enrollment or overcrowding was indicated by the magnitude of the absolute value of the ratio.

Overall, about one-quarter (26 percent) of public schools had enrollments within 5 percent of the capacity of their permanent instructional buildings and space (Figure 8 and Table 19). One third (33 percent) of schools had enrollments that were 6 to 25 percent below their capacity, and 19 percent of schools had enrollments that were more than 25 percent below their capacity. At the other end of the spectrum, approximately 14 percent of schools had enrollments that were 6 to 25 percent greater than the capacity of their permanent instructional buildings and space, and 8 percent had enrollments that exceeded their permanent capacity by more than 25 percent.

Thus, approximately half of schools were Under enrolled, about a quarter were near their capacity, and about a quarter overcrowded based on the capacity of their permanent instructional buildings and space. This translates into about 40,500 schools that were under enrolled, 20,400 schools at their capacity, and 17,400 schools that were overcrowded (not shown in tables).

The relationship between enrollment and building capacity was examined against various school characteristics (Table 19). The proportion of schools that were neither under enrolled nor overcrowded (i.e., schools that had enrollments within 5 percent of their capacity) differed somewhat by the school's instructional level and enrollment size. For instance, high schools were less likely than elementary schools to have enrollments within 5 percent of their capacity (28 percent versus 17 percent). In addition, small schools were less likely than medium and large schools to indicate that they had enrollments within 5 percent of their capacity (16 percent versus 29 percent and 30 percent, respectively).

Schools with enrollments that were 25 percent or more below their capacity might be considered severely under enrolled. The proportion of schools reporting enrollments that were 25 percent or more below their capacity varied by enrollment size, with the likelihood of being severely under enrolled decreasing with the school's enrollment size (Table 19). In addition, schools located in rural areas or small towns were more likely than those in central cities and urban fringe areas or large towns to be under enrolled by more than 25 percent of their capacity (27 percent versus 16 percent and 12 percent,
respectively). 43

The proportion of schools experiencing severe overcrowding (i.e., where enrollments exceeded capacity by more than 25 percent) differed somewhat by enrollment size, geographic region, and percent minority enrollment in the school (Table 19). 44 Large schools were more likely than small and medium schools to be overcrowded by more than 25 percent of their capacity (14 percent versus 4 percent and 5 percent, respectively).

Similarly, schools in the West were more likely than those in the Northeast or Midwest to be severely overcrowded (15 percent versus 4 percent and 5 percent, respectively). In addition, schools with more than 50 percent minority enrollment were more likely to report being severely overcrowded than were schools with 21 to 50 percent minority enrollment and those with 5 percent or less minority enrollment (15 percent versus 6 percent and 4 percent, respectively).

Together these data suggest that the majority of schools are either under enrolled or within 5 percent of their permanent capacity. School overcrowding, when it occurs, is present across all school characteristics, but more severe overcrowding (i.e., enrollments exceeding capacity by more than 25 percent) is more evident among schools with particular characteristics (see above). While potential reasons for this overcrowding were not explored in the survey, changes in public school enrollment growth may contribute to overcrowding. According to a 1999 report by the U.S. Department of Education (1999a), the West and the South led the nation in school enrollment growth, and cities and suburbs both experienced substantial school enrollment growth in the last 10 years. Enrollment growth in the West was particularly notable, increasing 26 percent from 1989 to 1999. During this time period, public school enrollment grew by 16 percent in the South, 14 percent in the Northeast, and 10 percent in the Midwest.

Overcrowding and School Condition

The work of Kozol (1991) and others suggests that in some public schools, overcrowding and crumbling buildings go hand in hand. According to this view, schools overburdened by too many students are likely to experience more wear and tear to their facilities. To examine the relationship between overcrowding and school condition, schools in this study were classified as being under enrolled, within 5 percent of their capacity, or overcrowded.

As noted earlier, 24 percent of all public schools reported at least one type of onsite building to be in less than adequate condition (see Table 3). This percentage varied based upon the relationship between enrollment and capacity within the school (Figure 9). Schools that were overcrowded were about twice as likely as schools that were under enrolled or within 5 percent of their capacity to indicate that they have at least one type of onsite building in less than adequate condition (43 percent versus 18 percent and 19 percent, respectively). Similarly, while 50 percent of all schools reported that at least one building feature was in less than adequate condition (see Table 4), this percentage varied based upon the relationship between enrollment and capacity within each school (Figure 9).

Schools that were overcrowded were more likely than schools that were either under enrolled or within 5 percent of their capacity to have at least one building feature in less than adequate condition (61 percent versus 47 percent and 48 percent, respectively). Finally, while 43 percent of all schools indicated that they had at least one environmental factor that was unsatisfactory (see Table 8), this percentage also varied based upon the relationship between school enrollment and capacity (Figure 9). Schools that were overcrowded were more likely than schools that were under enrolled or within 5 percent of their capacity to have at least one environmental feature in unsatisfactory condition (53 percent versus 41 percent and 39 percent, respectively). Thus, schools that were overcrowded were more likely to report facilities in less than adequate or unsatisfactory condition.

A closer examination of the adequacy of individual building features and satisfaction with individual environmental factors reveals the specifics of the poorer conditions of overcrowded schools compared with under enrolled schools and schools enrolled at their capacity, which tend to be similar to each other in condition. Among schools reporting at least one building feature to be in less than adequate condition, overcrowded schools reported significantly more features, on average, in less than adequate condition than did schools that were under enrolled (4.5 compared with 3.5; Figure 10). Schools with at least one unsatisfactory environmental factor reported, on average, between 2.4 and 2.9 unsatisfactory features, which did not differ significantly from each other.

Regarding the adequacy of specific building features, for all features except roofs and plumbing, overcrowded schools were significantly more likely than under enrolled schools to report the feature as less than adequate (Table 20).

Overcrowded schools were also more likely than schools within 5 percent of their capacity to report framing, floors and foundations, heating, ventilation, and air conditioning, and electric power to be less than adequate. Thus, overcrowded schools are generally more likely than other schools, particularly underenrolled schools, to suffer from a number of inadequate building features. Although there were no significant differences in the mean number of unsatisfactory environmental factors based upon the enrollment to capacity ratio categories of the schools, overcrowded schools were more likely than other schools to report some environmental features as unsatisfactory (Table 21). Overcrowded schools were more likely than either schools within 5 percent of their capacity and under enrolled schools to report unsatisfactory ventilation (38 percent compared with 24 and 23 percent). Overcrowded schools were also more likely than under enrolled schools to report unsatisfactory heating (25 percent versus 14 percent). Overcrowded schools were more likely than schools within 5 percent of their capacity to report unsatisfactory acoustics (25 percent versus 13 percent). The apparent differences between overcrowded and under enrolled schools in the likelihood of reporting unsatisfactory lighting, indoor air quality, or physical security based upon their enrollment to capacity ratio category were not statistically significant.

School Practices Used to Ease Overcrowding

Schools that suffer from overcrowding may utilize a number of strategies to ease the crowding. These strategies include modifying how physical structures are used, including investment in portable classrooms or using as classroom space rooms originally intended for noninstructional purposes. Other strategies utilize scheduling options, including staggered lunch schedules, year-round schedules, and split-day schedules. Because some of these practices may be used for purposes unrelated to overcrowding (e.g., providing additional instructional time or enrichment classes), respondents were asked to indicate whether the school used each practice, and if so, the extent to which the practice was used to ease overcrowding. The percentages of public schools nationwide that used each of these practices, and the extent to which the practice was used to alleviate overcrowding, are shown in Table 22.

Among the most common of the practices used by schools were strategies based on how space is used. Overall, 36 percent of schools reported using portable classrooms, and 20 percent reported the creation of temporary instructional space (Table 22). 45 This translates into about 28,600 schools using temporary classrooms, and 15,700 creating temporary instructional space (not shown in tables). For schools reporting the use of portable classrooms, about half (46 percent) reported doing so to a great extent in order to reduce overcrowding (Table 22). Among schools reporting that they created temporary instructional space, one-quarter (26 percent) reported doing so to a great extent in order to reduce crowding, while 34 percent did so to a moderate extent to ease overcrowding, and 38 percent did so to a minor extent. Few schools used off-site instructional facilities (8 percent) or used portable spaces other than for classroom purposes (9 percent). Among those schools that reported using the other space-related practices, about one-fifth of the schools did so to a great extent in order to reduce overcrowding.

Schools may also alter their schedules in order to reduce the number of students in a given space within the school at any given time. The most common of these scheduling practices was the use of staggered lunch schedules (74 percent). Of the schools using staggered lunch schedules, 45 percent reported doing so to a great extent in order to alleviate overcrowding, while 27 percent reported doing so to a moderate extent to ease overcrowding. 46 Very few schools utilized a year-round schedule (5 percent) or a split-day schedule (3 percent). Schools using a year-round schedule were nearly as likely to do so to ease overcrowding to a great extent (40 percent) as they were to do so for other purposes unrelated to crowding (36 percent).


40 Although overcrowding in schools is a frequent topic of discussion, particularly in the popular press, there have been no systematic and universally accepted measures of overcrowding. In the 1994 study, GAO attempted to measure overcrowding by collecting information about the number and total square feet of space in original buildings, permanent additions, and temporary buildings. GAO did not consider this attempt successful, and the data from these measures were not included in any of their reports. In a search of the overcrowding literature, we found that most measures consisted of subjective, self-report questions, such as "Is this school overcrowded?" For this study, we developed a measure based on the ratio of actual enrollment to building capacity.

41 The measure excluded capacity provided by temporary buildings and other temporary instructional space because these are often used to provide additional capacity for the school when overcrowding occurs. Including temporary buildings and instructional space would have obscured overcrowding at schools that use these to provide additional capacity for the school when the school enrollment exceeds the capacity of the permanent buildings and space. This decision was made during the survey development process in consultation with GAO staff who had worked on the 1994 study.

42 An interval was used rather than an exact point estimate match to indicate whether a school was under enrolled or overcrowded, since enrollment always fluctuates slightly at schools, and a small proportion of students above the building's capacity would be unlikely to severely strain the capacity of the school.

43 Note that differences that may appear large may not be statistically significant, due in part to the relatively large standard errors surrounding the estimates (because of the small sample size) and the use of the Bonferroni adjustment. These are discussed further in appendix A.

44 Some of the differences that may appear large may not be statistically significant due to the relatively large standard errors surrounding the estimates (in part because of the small sample size) and the use of the Bonferroni adjustment. See appendix A for a more detailed discussion.

45 Nationally, about 6 percent of instructional rooms were in temporary structures, and about 3 percent of instructional rooms were originally designed to serve non-instructional purposes (not shown in tables).

46 Note also that the use of staggered lunch schedules may reflect limited capacity of the cafeteria, which may be somewhat independent of the capacity of the school as a whole.

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