Apparent flaws in the Ordinary National Educational Test (O-Net) have provided another strong reminder that Thailand's education system badly needs improvement.

For years, agencies have lamented the falling average of O-Net scores among students in all subjects. But if O-Net exam papers are not really well designed and mired with mistakes, how can we expect the students to do well?

Thailand Development Research Institute (TDRI) academic Dr Dilaka Lathapipat pointed out that while the ISA test reflected the vision of the 21st century, Thailand's O-Net was stuck to the 20th century.

"The test-design standards for these two tests are much different," Dilaka said.