"There are 2,295 schools nationwide that failed to pass the assessment," Channarong Pornrungroj said on Thursday during a news conference on the results of the first phase of Onesqa's third round of external quality assessments.
The Onesqa's quality assessments of schools across the country is held every five years and the public organisation under the constitution conducted the assessment for a third time this year.
There are 12 key performance indices (KPIs) used to assess the quality of the schools such as students' learning achievements and the role of schools in extending education opportunities for students.
Mr Channarong said his organisation plans to conduct quality assessments for 34,040 schools this year with 7,985 so far having undergone the assessments.
He said of those being evaluated, 7,042 schools belonged to the Office of the Basic Education (Obec), 422 are under the Bangkok Metropolitan Administration (BMA), 328 under the Local Administrative Organisation (LAO), 191 under the Office of the Private Education Commission (Opec), and two demonstration schools under the Office of the Higher Education Commission (Ohec).
The assessment found 333 schools achieved an excellent standard and 5,357 were of a good standard. But 2,295 schools failed to meet the standard, he said.
He said most of the schools which failed the assessment were small and located in remote areas.
Mr Channarong said the biggest concern was that many schools achieved a low score in students' learning achievements.
"I think it resulted from the shortage of teachers in many schools and teachers themselves do not know how to develop their teaching patterns," he said.
To improve the students' performance, Mr Channarong proposed that correct answers of the Ordinary National Education Test should be given to the students after the exam so that they could learn the right answers.
Apart from the schools' quality assessments, Onesqa has conducted the third-round quality assessments for vocational institutions and universities this year.
Mr Channarong said 179 of 807 vocational institutions have so far undergone the assessments.
Of them, 106 got quality assurance and 53 received quality assurance with certain conditions. Twenty failed to pass the assurance test.
Forty-seven out of 72 universities have been evaluated. The assessments found 45 universities achieved quality assurance while two gained quality assurance with certain conditions.
"The universities should urgently upgrade the improvement of their teachers' knowledge," he said.
According to Ohec's data, there are 56,978 university lecturers countrywide but 38,238 of them (about 67%) had limited academic experience.
"We are worried about this, so more funds should be allocated to these lecturers to conduct more research," he said.