Just 21% of South Africa's 24793 public schools have libraries, according to the Department of Basic Education.

Experts called this "scandalous" and warned that school libraries were essential for the country to improve its poor literacy levels.

Limpopo, the Eastern Cape and Mpumalanga, the provinces that performed worst in the 2010 matric exams, have the fewest libraries in relation to the number of schools.

May figures said only 7.5% of Limpopo's 3924 schools, 9.7% of the Eastern Cape's 5676 schools and 17.3% of Mpumalanga's 1868 schools had libraries.

In the North West 321 of 1674 schools have libraries. More than half the schools in Gauteng - 1191 of 2031 - and the Western Cape - 775 of 1464 - have libraries.

Professor Genevieve Hart of the University of the Western Cape's department of library and information science, said these figures were "scandalous".

"The lack of libraries has a direct impact on the poor literacy levels." Improving literacy was the "number one reason to have libraries".

Annual national assessments, which test numeracy and literacy, will be released later this month. The department of basic education aims to improve numeracy and literacy levels of Grade 3 and 6 pupils to at least 60%, by 2014.

Hart said access to a library improved general academic performance since reading strengthened interpretational abilities.

Althea Hofmeyr, who has conducted research over six years for institutions such as the Wits School of Education and US Aid - based on classroom observations - said she often found schools with libraries did not use them properly.

"They are used as store rooms or the books lie in heaps on the floor.

"Sometimes the library looks so beautiful the librarian doesn't want the children to touch the books.

"Having no library stifles development. Children are reduced to [reading] what teachers write on the board and what textbooks say."

The Department of Basic Education did not answer questions sent on Friday. Spokesman Granville Whittle said they would only be able to reply today.