The basic education department claimed this week that schools in South Africa have an average of 30 pupils per classroom. But educationalist have lambasted the estimation, saying it is a "distortion" of reality.
The figure appears in the Annual Schools Survey: Report for Ordinary Schools 2010 and 2011, which the department posted on its website on September 30.
This publication followed the Mail & Guardian's analysis last week of leaked raw data for 2012 that covered essentially the same indicators as the department's report ("Crisis in our schools", September 27).
These indicators include number of schools, enrolment patterns, pupil deaths, schoolgirl pregnancies, income from school fees and the home languages of pupils.
"In 2011, the national average class size in ordinary schools was 30," this week's published report said.
But "the national average of 30 pupils per class hides large differences between public and independent schools", said Stellenbosch University education researcher Nic Spaull.
"Independent schools often charge school fees and thus can supplement government funding with fees from parents, leading to smaller class sizes."
Dr Jabulisile Ngwenya, of the University of KwaZulu-Natal's school of education, believes that "if you give an average national figure for class sizes you are distorting everything".
This is because the average does not adequately reflect enormous class size differences between rural, township and former model C schools.
Using KwaZulu-Natal as an example — the department's report said the province has an average of 39.5 pupils per class — Ngwenya said: "The reality is that if you go to many schools in rural areas they have 60 to 70 pupils in a single classroom."
The department appears to have arrived at the figure of 30 by adding average class sizes for public and private schools and dividing by two.
But educationalists said this procedure is statistically flawed because the country's 1 455 private schools in 2011 constituted only 5.7% of the total. There were more than 25 700 (94.3%) public schools that year, the report said.
The report concedes that "the national average conceals interprovincial inequities" and that the "figure [of 30] hides the impact of low class sizes in independent schools on the national average".
"On average though, all provinces fall within the acceptable class size norm of 40 pupils per classroom," it said. But educationalists vehemently disagreed with this assessment of "acceptability".
"Schools in townships and informal settlements are overcrowded," said Reuben Lechesa, secretary of the National Association of School Governing Bodies in the Johannesburg region.
"Schools in Cosmo City [near Johannesburg] are actually overflowing."
Annette Lovemore, the Democratic Alliance's basic education spokesperson, said the department's calculation of class size is "entirely disingenuous".
"It is essential to record and understand individual circumstances, in order that no class is bigger than the recommended norms."
In May, Basic Education Minister Angie Motshekga confirmed to Parliament in a written reply to Lovemore that the department "does not maintain a database of actual class sizes in each school".
Regarding other indicators, last week's M&G story concluded there were enormous disparities in the health and wellbeing of children in different provinces. These disparities are equally evident in the 2010-2011 survey published this week.
For instance, nearly 700 Free State pupils died, compared with 300 in the Western Cape — a rate similar to the 2012 pattern the M&G revealed.
On the other hand, schoolgirl pregnancies appear to have been falling year on year over the past three years. The raw data for 2012 suggested nearly 30 000 pupils were pregnant that year, the M&G reported.
This is a considerable decrease from figures the department's published report reflect: 36 700 in 2011 and 45 200 in 2010.
In a decrease educationalists welcomed, multigrade classes — those in which pupils in more than one grade are taught in the same classroom at the same time — declined from 26% in 2010 to 21% in 2011, the report said.