Bond measures Skyline Elementary
Student teacher Elisse Bevilacqua teaches a class inside a portable at Skyline Elementary in the Solana Beach School District. April 12, 2016. Megan Wood, inewsource

One striking thing about Scripps Ranch High School is how typical it looks. Opened in 1993, it’s not particularly modern, but it doesn’t seem outdated. Teal stripes accent the tan walls so familiar to San Diego students and teachers. Two-story buildings face a circular courtyard.

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[box type=”shadow this-matters”]School districts have relied on the structures for decades, even as officials consider health risks and impacts on learning.[/box][/one_half]

In a rear parking lot is another common feature — portable classrooms.

In a countywide survey, inewsource found that almost one in five classrooms in 35 school districts are portable.

These cheap and easy structures have been flagged for poor ventilation, and they are often either too hot or too cold. The sounds inside can be loud enough to justify a noise complaint. In Scripps Ranch, skunks and flooding have plagued the portables. In addition to health concerns, studies show school surroundings can negatively affect a student’s ability to learn.

The structures, also known as modular or relocatable classrooms, are less expensive to build than permanent classrooms and can be put in place quickly to meet unexpected changes in enrollment. State policies and financial incentives over the years also have encouraged school districts to rely on portables.

Scripps Ranch High teacher Julia Knoff has spent her entire career in those rows of portables.

“I’ve been teaching in a parking lot for 20 years,” Knoff said.


Graphic by Jorge Contreras, KPBS

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When she started teaching history in classroom B13, Scripps Ranch “was two years new at that point and there were already 17 portable rooms.”

Click here to search the number of portables at your school

Since then Knoff has moved a few times, never to a permanent classroom. Instead, the number of portables at the school has more than doubled to one in every three classrooms. Hers is one of almost 1,500 portable classrooms in the San Diego Unified School District, according to data gathered by inewsource.

Still, Scripps Ranch is barely in the top 50 schools in the district when it comes to share of portable classrooms. In some elementary schools, including Kumeyaay in Tierrasanta and Rowan in Fairmount Park, more than half of all classrooms are portables.

The use of portables follows no discernible economic or geographic pattern. At Marshall Elementary in Chollas Creek, virtually all students receive free or reduced lunch, and at Dingeman Elementary in Scripps Ranch fewer than one in 10 students do. But at both schools about 53 percent of classrooms are portables.

Julia Knoff has taught history in a portable classroom at Scripps Ranch High School for 20 years. April 18, 2016. Megan Wood, inewsource
Julia Knoff has taught history in a portable classroom at Scripps Ranch High School for 20 years. April 18, 2016. Megan Wood, inewsource

Jerabek Elementary in Scripps Ranch is 58 percent portables, the second highest number in San Diego Unified. Parents there agreed quality facilities affect students’ learning.

Andrea Potterat had two children graduate from Jerabek. She was picking up students at the school for a neighborhood carpool on a recent afternoon.

“I think that if you are in a rundown, decrepit building, it probably does not invigorate you or give you a sense of joy in your space and your day,” she said.

Potterat called the portables at the school “a real problem,” citing the ratio of students per square footage in the classroom. She said they were “some of the last built on-site portables.”

“Some of those rooms really just look like plywood walls,” she said.

Not all parents dislike the structures.

Peter Schwartz has a fourth-grader at the school.

“In a lot of ways I think they’re nicer and newer classrooms,” Schwartz said. “I think they had air conditioning before the rest of the school.”

Anastasia Zamiara, a fourth-grader at Jerabek, said the portables offer some advantages.

“We have a heater and we have an air conditioner and windows that the other classrooms don’t,” Zamiara said.

More than 30 portable classrooms sit in the back parking lot of Scripps Ranch High School in this undated photo. Megan Wood, inewsource
More than 30 portable classrooms sit in the back parking lot of Scripps Ranch High School in this undated photo. Megan Wood, inewsource

Portables aplenty

inewsource has embarked over the past few years on an intermittent series exploring factors that might explain inequities in public school education, including financial and physical differences among districts and schools themselves. We requested data on the number of portable and permanent classrooms from all school districts throughout San Diego County.

Of the 42 districts in the county, 37 provided data. They had a combined 4,590 portable classrooms, more than all of those used in the entire state of Washington, which has a population of 7.1 million people.

Overall, portables account for almost 23 percent of classrooms in San Diego County districts that provided data.

The share of portables among districts varied widely, especially among smaller elementary districts. At Vallecitos School District in Rainbow, eight of its 12 classrooms are portables, and at Rancho Santa Fe School District, all of its 62 classrooms are permanent.


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Click here to search portables at your school and district


The Escondido Union School District had the highest share among districts that have at least 5,000 students, with portables making up 45 percent of its elementary and middle school classrooms. Its counterpart, the Escondido Union High School District, had 7 percent portables, which was among the lowest shares for districts with an enrollment of 5,000 or more.

California does not have specific rules about how many portable classrooms are acceptable, and the only major research into portable classrooms was a comprehensive 2004 study of more than 200 classrooms statewide from the California Air Resources Board.

That study looked at “environmental health conditions” in portable classrooms, and it found a variety of concerns, including “inadequate ventilation” during 40 percent of the classroom hours monitored.

Research has shown the overall quality of school facilities can affect learning. Limited research into portables suggests they can negatively impact student success.


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One study found a correlation between a reduction of portable classrooms in rural schools in Texas and improved standardized test scores.

And a University of Houston study showed a relationship between large numbers of portable classrooms and student dropouts and absences, especially at the high school level.

Peggy Jenkins is a manager at the California Air Resources Board. She was one of the principal authors of the study on environmental effects of portable classrooms.

“It’s not just a comfort issue, but inadequate ventilation leads to increased carbon dioxide levels, which we now know can produce some issues at very high levels,” Jenkins said. Mixed with high moisture, poor ventilation can also lead to mold growth and other problems.

The study found that fresh air didn’t always get in, but noises certainly did.

“About one half of (classrooms) exceeded 55 decibels, which is the level that many communities use to regulate their outdoor nuisance noise level,” Jenkins said.

Those two issues have a common cause: heating, ventilation and air conditioning systems.

“The teachers often felt they needed to turn them (AC) off because they were so loud they couldn’t hear the students and the students couldn’t hear the teachers,” Jenkins said. “And, of course, as soon as you turn them off then there’s no air exchange, no ventilation.”

That can lead to uncomfortable temperatures, which the Air Resources Board study found in a quarter of classrooms it studied.

At Scripps Ranch High, the window AC units don’t circulate the air enough to get the whole classroom, “so the side of the room where the window unit is is really cold and the side where it’s not is really hot,” Knoff said.

When it gets hot, the AC can have trouble keeping up.


Two rows of portables sit across from each other in Solana Vista Elementary in the Solana Beach School District. April 12, 2016. Megan Wood, inewsource

Read part 2: Portable classrooms not always the right answer to school money question


“I’ve had (the AC unit) shut down on a day where it was over 100 degrees at Scripps Ranch, and the inside of my room was 110 degrees,” she said.

Opening a window can be trouble. Because of how close the portables are to each other, a window might back up to another classroom’s AC unit, blowing in hot air. And a teacher “who has a more projected voice,” Knoff said, might drown out a neighboring teacher.

Lee Dulgeroff is the chief of facilities planning and construction at San Diego Unified. He said portables “tend to be a little louder than the traditional classroom because they lack some of the insulation.”

They also have more walls exposed to outside noises.

And unlike permanent buildings, the only way in and out of a portable classroom is via those bright — and sometimes hot — aluminum walkways.

That can be really noisy, Knoff said.

“If you’re in your classroom and you’re doing your thing … and the teacher next door is taking their students to the library, there’s not stairways right in front of their classroom,” she said. “It’s 36 kids walking, and there’s nothing you can do. They are just loud because of the nature of what it is. So it’s a distraction until they go by.”

The Air Resources Board study didn’t measure all the challenges with portables because some are unique to a school.

At Scripps Ranch, Knoff said, the parking lot where her classroom sits can have some drainage issues, so much so that one year a principal refused to visit those classrooms during a rainy period.

And then there are the skunks. Generally, portables are elevated, so despite planks or other material, animals find a way into the space.

“Every year there’s a day or two where it smells so bad in there you can’t actually teach because the spray is so strong, ” Knoff said.

Dulgeroff said newer portables have mostly addressed issues such as poor ventilation, though he acknowledged there are advantages to permanent structures.

“I think overall the (state) study is correct that generally speaking, permanent classrooms tend to be a better teaching and learning environment,” he said.

Students and teachers can only go in and out of the portables at Scripps Ranch High through aluminum walkways. Megan Wood, inewsource
Students and teachers can only go in and out of the portables at Scripps Ranch High through aluminum walkways. Megan Wood, inewsource

A new hope

Health concerns aren’t the only motivation for getting rid of portables. Permanent buildings can be two or more stories tall. Removing one-story portables can free up space, in playgrounds, for example.

“So it tends to be a better fit for us to replace those (portable) buildings as we can, little by little,” Dulgeroff said.

Replacement of portables is a San Diego Unified long-term goal, he said.That has reduced the number of portable classrooms in the district from a one-time high of around 3,000 to the current 1,500, Dulgeroff said.

That might soon include Scripps Ranch. According to San Diego Unified, a modernization project for that high school includes a new permanent, two-story building that will replace 12 portable classrooms. The rooms will have all the trimmings of a modern school: smartboards, microphones and tablets for the teacher and netbooks for the students.

Construction of the new building is expected to start near the end of 2016 and is estimated to cost $5 million to $10 million.

The prospect of a brick-and-mortar classroom excites Knoff.

“I’ve taught for a long time and I absolutely, positively love my job. I still love kids, you know. I still love what I do and I think it’s all really awesome,” she said. “But I wish that in my professional career I had what feels like a privilege to go teach in a building.”

Investigative Assistant Madison Hopkins contributed to this report. 

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Leonardo Castañeda was a reporter and economic analyst for inewsource. To contact him with tips, suggestions or corrections, please email leocastaneda [at] inewsource [dot] org.