Here are the most recent class sizes for every public, separate and charter school in Alberta

As students prepare to return to school in the age of COVID-19, class sizes have taken on a new meaning, but the Alberta government is no longer publishing up-to-date class-size data.

Data is one year out of date but it's the best available, after Alberta ended class-size reporting requirement

Students are seen in a classroom in Calgary in this file photo. Class sizes have taken on new meaning for many parents in the 2020-21 school year, given the COVID-19 pandemic. (CBC)

UPDATE — Aug. 14, 2020: After many readers asked for finer detail on the class-size distributions, we've changed the "buckets" in the tables to show the percentage of class sizes with 15 or fewer students, 16 to 20 students, 21 to 25 students, 26 to 30 students, and more than 30 students.

Original story below.

Last fall, the Alberta government ended its longstanding practice of tracking and publicly reporting the number of students in every class at every public, separate and charter school in the province.

At the time, the move received some criticism, largely from policy wonks, data analysts and interested parents who were willing to go down the deep rabbit hole of information that used to be available.

But now, as students prepare to return to school in the age of COVID-19, class sizes have taken on a new meaning.

No longer is class size just seen in terms of how it affects student learning; it's also seen as a risk factor for contracting the novel coronavirus.

So if you're a parent wondering not only about the size of your own child's class, but also the size of other classes in the same school, and how that compares with other schools, you're not able to access that data in the same way as you were in the past.

But the data for the 2018-19 school year — the most recent year for which detailed numbers were consistently reported — is still available and offers at least some sense, albeit one that is a little out of date.

Below you'll find that class-size information for 1,570 schools in Alberta.

There are four searchable tables, each showing class-size info for a different grade group: kindergarten to Grade 3, Grades 3 to 6, Grades 7 to 9 and Grades 10 to 12.

In the past, this data has often been presented in terms of average class size or the number of classes that exceed target guidelines for a particular age range.

But in light of the pandemic, many parents are wondering about the sheer scale of kids in the classroom, so in the tables below we've broken down the data to show class-size distribution — that is, the percentage of classes at a given school that had 15 or fewer students, 16 to 30 students, 31 to 45 students or more than 45 students. (These distributions have been updated; see note at top.)

Sean Dunn wishes this same type of data was available for the most recent school year.

He is a parent of two school-aged children, the husband of a teacher and a volunteer with Support our Students Alberta, an advocacy group for public education.

He's also a data expert and last year produced a report for Support our Students. It delves deeply into the data that does exist.

But even before that, simply as a father, he would pore over the annual class-size datasets out of personal interest.

"As a parent, it matters to me what my own class sizes are — and it matters even more in a pandemic," he said.

"And not only that, but what are the class sizes in that school?"

From 2004 to 2019, the Alberta government annually published detailed class-size data online. Collectively, these annual reports create a massive dataset comprising 2.8 million rows of information.

"It was very fine-grained," Dunn said.

"It listed every single class for every single school year, which subject, which school district, which grade.… It really allowed you to slice the data many different ways."

He worries the loss of that data will have an impact on "evidence-based decision making."

"The other aspect is the public transparency perspective where now, we as the public, simply don't know what the situation is anymore," he said.

But the provincial government says information on class sizes is still available to parents, upon request.

"Individual schools still have this information, and school authorities can easily access it through school records," Colin Aitchison, the press secretary to Education Minister Adrian LaGrange, said in an email.

"If a parent is looking for information on their child's class or other classes in their school, they should contact their principal or school authority."

Jason Schilling isn't so sure that approach is particularly useful for parents — or teachers.

He's the president of the Alberta Teachers' Association, which filed multiple freedom of information requests to individual school authorities (at $25 per request) in an attempt to get class-size information that used to be publicly available for free.

The results were mixed.

Some authorities, like the Parkland School Division, provided the ATA with detailed data on the sizes of each class in each school.

Others, like the Edmonton Public School Board, responded with aggregated information that included class-size averages but not individual class sizes.

Others still, like the Calgary Catholic School District, provided class-size averages with a cautionary note that the data is not reliable and "may lack comparability with class-size average information for previous years."

Much of the data that was received came in various, inconsistent formats. One school authority provided a scan of a timetable with what appears to be class sizes written in, by hand, in pencil. Another provided a text file with information buried in a numbering scheme that needed to be decoded.

Examples of class-size data obtained by the Alberta Teachers' Association through freedom of information requests from the Battle River School Division, at top, and Lethbridge School Division, at bottom. (Screenshots)

Schilling said it's a far cry from the consistently gathered and reported class-size data that Alberta had been publishing for the past decade and a half.

"It's difficult [now], because you have holes in the data," he said.

While individual teachers know how big their class will be for an upcoming semester, Schilling said the ATA used the provincewide class-size data for a variety of purposes, including negotiations in its collective bargaining with the province.

He also said detailed and consistent data would be helpful for public health purposes in the near future, when evaluating how well various measures to curb the spread of COVID-19 have fared.

Aitchison noted the requirement for class-size data reporting was initially created alongside provincial grants aimed at bringing class sizes down.

Since class sizes have actually increased over the past 15 years, he said the provincial government decided to scrap the whole thing

"During the election we committed to Albertans to conduct an immediate audit to determine what happened to previous funding dedicated to class-size reduction," he said.

"What we found was that this funding was ineffective and did not succeed in reducing class sizes. The reporting was tied to this failed grant."


Robson Fletcher

Data Journalist

Robson Fletcher's work for CBC Calgary focuses on data, analysis and investigative journalism. He joined CBC in 2015 after spending the previous decade working as a reporter and editor at newspapers in Alberta, British Columbia and Manitoba.