In a high school, everybody is moving at the same time. Different directions, different destinations, different goals. Students land in different classrooms with different classmates and different teachers. What's so tough about planning a space like that?
Experienced educational planners know that conflict can flare up easily when high schools hold focus-group meetings to plan facility upgrades. Department chairs and staff members march into a conference room and spell out their needs. The longer the meeting, the more bloated their department — their territory — seems to become.
The planned project (an addition, for instance) can quickly veer into problem areas: too big, too expensive and too inefficient. “Architects!” superintendents and boards grumble. “They're going to chew me up and spit me out,” thinks the planner.
One way to avoid such a conflict is a data-driven program analysis. This enables planners to gather information about the variables for a high school and use the data to reach conclusions about the school's space needs. The analysis must be based in fact and customized for every school. All space needs must be sensitive to all variables:
- Enrollment.
- Class size.
- Periods per day.
- Building utilization (efficiency).
- Number of staff required.
- Classroom size.
- Programs offered (classes).
The result is a programming tool that allows focus groups to have their say and gives the “powers that be” an easy way to review or modify the variables to match a school's goals and budget. The same tool ensures that every high school space built is program-driven and customized for that high school's curriculum, graduation requirements and student enrollment patterns.
Using the data appropriately, administrators can calculate a school's current capacity and its future expansion needs. There are many ways to measure capacity; these differing measurements can be examined by changing the variables. Because the number and types of spaces define program capacity, different programs (particularly special ones such as music, art and life skills) can have different capacities. Calculating capacity for an existing building essentially is an exercise in reverse space programming.
Making up your mind
Here are some key steps to determining a high school's capacity and needs:
- Existing building information
Programming for an addition is more complex than programming for a new building; with an addition, the existing building must serve a portion of the overall programmatic needs. The first step requires categorizing every space or classroom that will be scheduled for student use. The resulting Existing Room Database (Figure 1) documents characteristics such as academic category, square footage and use for each space. Although most high school space types are similar, some spaces are unique to an institution or district.
The size or shape of some spaces may not meet needs or standards; these spaces should be re-categorized. This is not uncommon, especially in older schools where many classroom areas are about 600 square feet (200 to 300 square feet smaller than planned new classrooms). As many of those older classrooms as possible should be reclassified from “regular classroom” to “small classroom” for use as pullout resource space or other special services.
- Course catalog descriptions
Analyzing the course-catalog descriptions helps define classroom types needed for each course, target class size, and (sometimes) specific classroom activities that may affect space requirements and class size. Based on this, establish target class sizes used globally for all classes. This customizes the building program to fit with the school curriculum.
The example in Figure 2 shows Freshman English 1, 2 is offered in Regular (R), Intermediate (I) and Advanced (A) formats. The Class Size Table (Figure 3) shows the target class sizes for each option. Class size affects capacity, but so do enrollment levels in various class formats (basic, college prep, honors, or AP). Note that class size will turn out to be an average across the sections required.
Class format helps identify target class size and classroom type. For instance, in Figure 4, science labs have 24 lab stations, so the target class size is 24 students, and the classroom type is a science lab (L). On the other hand, Freshman English 1, 2 would take place in a regular classroom with a target class size of 28 students (see Figures 2, 3). Note that the size of the regular classroom actually is designed for 30 students to accommodate normal fluctuations in class size. This extra space avoids classroom crowding when districts must create larger than desirable sections. More stringent restrictions are enforced on the science lab that has 24 stations for 24 students.
- Student participation
Determining student participation by course requires comparing the number of students enrolled in a course with total school enrollment. Reviewing three to five years of enrollment helps detect and project enrollment trends. These projections are used if a district wants to mold enrollment patterns toward specific academics or modify graduation requirements.
Figure 5 shows enrollment data for a Freshman English 1, 2 course at one high school. It shows 2.29 percent of the students taking Regular (R) Freshman English, and 20.13 percent taking Intermediate (I) Freshman English. Every class in every department should be included to build a classroom needs picture for all programs in the entire high school. The percentages are constant, while the variables are altered to calculate capacity or need.
Derive the number of sections by looking at class size and class enrollment. Figure 6 shows that Intermediate Freshman English 1, 2 will require 19 sections. Class enrollment is calculated by multiplying the total enrollment (2, 523) by the participation rate (20.13 percent), which equals 508. The class enrollment is divided by the target class size (28 students). The result? The school will need 19 sections.
- Spaces required
The number of spaces required to deliver each course is based on the number of sections for that course, the number of periods per day a course requires (i.e., one for English 1, 2), and the frequency of meeting in days per week (typically five). This is then translated into an actual number of rooms required based on the number of times (periods) each room is available per week (seven periods per day, five days a week equals 35). The sample calculations continue as follows for Intermediate Freshman English:
-19 sections per day multiplied by one period per day and five days per week equals 95 classroom periods needed per week.
-95 periods per week divided by 35 room periods per week equals 2.7 rooms required (every school day).
Thus, Freshman English 1, 2 (I) requires 2.7 regular classrooms every day of the week to serve 20.13 percent of a student enrollment of 2,523. This calculation is shown at an idealized 100 percent building utilization factor (see sidebar, “What is Building Utilization?” p. 186).
A more realistic utilization factor is 85 percent. This means classrooms will be used about seven of eight periods. This provides the flexibility to avoid many scheduling conflicts. It also means some teachers cannot “own” classrooms for a few periods a day, and others get no “regular” classroom. But classrooms are too large to use only five periods a day (62 percent utilization). A school that wants “high” capacity utilization can be set to 90 percent or a little higher. For Freshman English (I) in our example, 2.7 divided by 0.85 equals 3.2 classrooms that can be planned to accommodate this program — no more and no less.
- Program capacity
After doing similar calculations for every class, schools can determine requirements for every kind of delivery space, then compare it with the existing building classrooms. To determine the capacity, roll back enrollment or raise utilization until the number of required delivery spaces is equal to the number of existing spaces. Figure 7A indicates a capacity of 1,623 students at 90 percent utilization. This particular school could accommodate more students by increasing class sizes. Also note how this school has more “standard use” classrooms than required at this enrollment. More core curriculum courses and classrooms could be scheduled, increasing capacity, while capping special programs as needed. This is one of many views of this high school's capacity based on the program and driven by the data.
Figure 7B shows the spaces needed to achieve a demographer's projection of an increase in student enrollment to 2,523 students. Line 3 shows 24 new classrooms, one new science lab, etc., are needed to operate at these class sizes and this building utilization. Of the 73 total regular classrooms, 3.2 classrooms are for English 1, 2 (I).
Because of these variables, high school enrollment capacity is a topic that is sorely misunderstood by many. Some people insist on an unwavering number, when in truth, the capacity can be manipulated by several variables.
Because no standard exists for establishing high school capacity, reaching consensus on capacity can be complicated. How many planners have seen administrations and school boards counting classrooms and multiplying by that elusive class size, or witnessed school boards argue over scheduling efficiency, why it is needed, and what it should be? How many times have administrators considered limiting the number of classes students will be allowed to take or even direct their principals to count the seats in each room?
None of these address what is most important: school buildings, like textbooks, are tools for meeting student needs. Program-driven capacity best enables administrators and teachers to accomplish their core mission of teaching and learning.
McDonough, AIA, specializes in educational planning and programming for Legat Architects, Inc., an architectural firm based in Waukegan, Ill.
What is building utilization?
Building utilization is the amount of use space gets compared with its total availability. It may seem that 100 percent utilization is a desirable goal, but that is not the case in a high school. Student enrollment demands and choice do not permit every seat in every classroom to be filled every period of the school day.
Building utilization is inversely proportional to the flexibility of a high school. The school loses the ability to respond to student class requests if no spaces are available, no sections are available during that period, or a classroom is already crowded. Higher efficiencies cause more scheduling conflicts and result in more students not getting their first choices.